Pitfalls in spontaneous in vitro transformation of human mesenchymal stem cells

Spontaneous in vitro transformation of human primary cells was, and continues to be, a scarcely described phenomenon. Only the description of the generation of the HaCAT cell line [1] is a canonical example, worldwide accepted. More recent examples included the emergence of tumorogenic populations upon in vitro culture of fetal human mesenchymal stem cells (hMSC), induced by GM-CSF and IL-4, [2] and bone marrow hMSC [3]. Other examples have also been reported after very long-term in vitro culture of telomerized hMSCTerT [4]. In this scenario, our previous results [5-7] were only a new observation to be added to this list. Only very recently similar results have been published [8], reporting spontaneous malignant transformation in 46 % of bone marrow–derived hMSC long-term cultures (5–106 weeks). However, other authors reported opposite results.S

Combined pulsed electric field and high-power ultrasound treatments for microbial inactivation in oil-in-water emulsions

[EN] The impact of individual and combined pulsed electric field (PEF) and high power ultrasound (HPU) on the inactivation of different microorganisms in emulsions was investigated. The highest inactivation level using PEF was 2.6, 1.2 and 0.1 log-cycles for Escherichia coli, Aspergillus niger and Bacillus pumilus, respectively, achieved at the highest energy level and temperature (152.3-176.3 kJ/kg and 25 degrees C). HPU led to the highest reduction (5.4, 4.3 and 0.3 log-cycles for E. coli, A. niger and B. pumilus, respectively) after the longest treatment time studied (3 min). PEF (152.3-176.3 kJ/kg) followed by HPU (3 min) was found to be the most effective sequence, leading to synergistic effects (6.6 and 1.0 log-cycles for A. niger and B. pumilus, respectively), compared to the individual treatments. PEF-HPU is a promising hurdle technology with which to inactivate vegetative bacteria or fungal spores in emulsions. However, limited inactivation was achieved for bacterial spores.The authors acknowledge the financial support from Fresenius KabiGómez-Gómez, Á.; Brito-De La Fuente, E.; Gallegos, C.; Garcia-Perez, J.; Benedito Fort, JJ. (2021). Combined pulsed electric field and high-power ultrasound treatments for microbial inactivation in oil-in-water emulsions. Food Control. 130. https://doi.org/10.1016/j.foodcont.2021.108348S13

Statistical analysis of an experimental database on residual flexural strengths of fiber reinforced concretes: performance-based equations

The postcracking capacity of fiber reinforced concrete (FRC) mainly depends on the content, material, and geometry of the fibers considered. Even though the general influence of these factors on FRC behavior has been extensively addressed, the uncertainty of the FRC performance prediction along with the variability of the results still poses a challenging issue that needs to be solved to encourage the use of FRC for design and construction purposes. In this line, a database including the results of the flexural residual strength obtained from different experimental programs combined with the results of previous studies has been gathered and analyzed herein to obtain general correlations and trends providing additional information about the influence of the fibers in FRC behavior, these meant to serve for initial design stages (e.g., make decisions on the type and amount of fibers based on technical and economical requirements). The results are analyzed distinguishing between the fiber material, the fiber shape, the aspect ratio and tensile strength. The results presented herein may provide valuable information on the initial prediction of the residual strength of FRC to fully take advantage of the mechanical properties of the material.The authors from UPC wish to express their acknowledgment to the Ministry of Economy, Industry and Competitiveness of Spain for the financial support received under the scope of the projects BIA2016-78742-C2-1-R and PID2019-108978RB-C32.Peer ReviewedPostprint (published version

Environmental effects of using different construction codes applied to reinforced concrete beam designs based on Model Code 2010 and Spanish Standard EHE-08

Assuming specific behavior models, the variety of design codes currently used for the design of concrete beams inevitably results in different solutions, ensuring service during the expected lifetime with a maximum functional quality and safety. However, from a sustainable design perspective, such differences may have remarkable environmental impacts. This paper analyses if the approach of the newest design code, i.e., the Model Code, leads to a reduction in resource consumption and greenhouse gas emissions (GHG) over the life cycle of concrete beams. To do so, a comparative analysis of the environmental impact of concrete beams was carried out depending on the reference code used for their design (i.e., EHE-08 or Model Code). The results show that reducing the amount of reinforcing steel is essential to minimize the life cycle environmental impacts of concrete beams. Every country may have its own design codes and, thus, the reinforcing steel use can vary for structures subjected to the same loads and with equivalent structural reliability. Hence, regulations play a key role in the sustainability of construction assets. Conclusions depend on the beam’s length (L), height (h) and characteristic compressive strength (fck). For short beams (4 m), the greater the h, the greater the reinforcement difference between the two codes. With regard to beams with L = 8 m, these differences can lead to varying steel and GHG savings, e.g., up to 5.0 % with MC-2010 (h = 0.6 m and fck = 35 MPa), almost 40 % with EHE – 08 (h = 0.6 m and 35 MPa < fck = 50 MPa) and more than 30 % with MC-2010 (h = 1.0 m).. For long beams (L = 12.0 m), steel consumption is 0.3 % to 19 % lower when the beam is designed with EHE-08, and this difference decreases as fck increases.Peer ReviewedPostprint (author's final draft

Gene silencing in tick cell lines using small interfering or long double-stranded RNA

Gene silencing by RNA interference (RNAi) is an important research tool in many areas of biology. To effectively harness the power of this technique in order to explore tick functional genomics and tick-microorganism interactions, optimised parameters for RNAi-mediated gene silencing in tick cells need to be established. Ten cell lines from four economically important ixodid tick genera (Amblyomma, Hyalomma, Ixodes and Rhipicephalus including the sub-species Boophilus) were used to examine key parameters including small interfering RNA (siRNA), double stranded RNA (dsRNA), transfection reagent and incubation time for silencing virus reporter and endogenous tick genes. Transfection reagents were essential for the uptake of siRNA whereas long dsRNA alone was taken up by most tick cell lines. Significant virus reporter protein knockdown was achieved using either siRNA or dsRNA in all the cell lines tested. Optimum conditions varied according to the cell line. Consistency between replicates and duration of incubation with dsRNA were addressed for two Ixodes scapularis cell lines; IDE8 supported more consistent and effective silencing of the endogenous gene subolesin than ISE6, and highly significant knockdown of the endogenous gene 2I1F6 in IDE8 cells was achieved within 48 h incubation with dsRNA. In summary, this study shows that gene silencing by RNAi in tick cell lines is generally more efficient with dsRNA than with siRNA but results vary between cell lines and optimal parameters need to be determined for each experimental system

Aspergillus Metabolome Database for Mass Spectrometry Metabolomics

The Aspergillus Metabolome Database is a free online resource to perform metabolite annotation in mass spectrometry studies devoted to the genus Aspergillus. The database was created by retrieving and curating information on 2811 compounds present in 601 different species and subspecies of the genus Aspergillus. A total of 1514 scientific journals where these metabolites are mentioned were added as meta-information linked to their respective compounds in the database. A web service to query the database based on m/z (mass/charge ratio) searches was added to CEU Mass Mediator; these queries can be performed over the Aspergillus database only, or they can also include a user-selectable set of other general metabolomic databases. This functionality is offered via web applications and via RESTful services. Furthermore, the complete content of the database has been made available in .csv files and as a MySQL database to facilitate its integration into third-party tools. To the best of our knowledge, this is the first database and the first service specifically devoted to Aspergillus metabolite annotation based on m/z searches

Copper: Synthesis Techniques in Nanoscale and Powerful Application as an Antimicrobial Agent

Nanosized metal particles show specific physical and chemical properties that allow the creation of new composites materials, which are important for multiple applications in biology and medicine such as infections control. Metal nanoparticles, mainly copper, exhibit excellent inhibitory effect on Gram-positive and Gram-negative bacteria; therefore the exploration about the efficient, economical, and friendly environmental technics to synthesize inorganic nanoparticles is imperative. In this work a brief overview of the several methods is made including the comparison of the methods, mainly between sonochemical, microwave, and chemical routes. It allows determining the optimal parameters and technical conditions to synthesize copper nanoparticles with physical and chemical properties suitable for the oral bacterial inhibition

Permanent magnetism, magnetic anisotropy, and hysteresis of thiol-capped gold nanoparticles

We report on the experimental observation of magnetic hysteresis up to room temperature in thiol-capped Au nanoparticles with 1.4 nm size. The coercive field ranges from 860 Oe at 5 K to 250 Oe at 300 K. It is estimated that the Au atoms exhibit a magnetic moment of mu=0.036mu(B). However, Au nanoparticles with similar size but stabilized by means of a surfactant, i.e., weak interaction between protective molecules and Au surface atoms, are diamagnetic, as bulk Au samples are. The apparent ferromagnetism is consequently associated with 5d localized holes generated through Au-S bonds. These holes give rise to localized magnetic moments that are frozen in due to the combination of the high spin-orbit coupling (1.5 eV) of gold and the symmetry reduction associated with two types of bonding: Au-Au and Au-S