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Lipid biosynthesis is a significant metabolic response to nitrogen starvation in oleaginous fungi. The oleaginous fungus Mucor circinelloides copes with nitrogen stress by degrading AMP through AMP deaminase (AMPD). However, the mechanism of AMPD in regulating lipogenesis remains largely unclear. To elucidate the mechanism of AMPD in lipid synthesis in this M. circinelloides, we identified two genes (ampd1 and ampd2) encoding AMPD and constructed an ampd double knockout mutant. The engineered M. circinelloides strain elevated cell growth and lipid accumulation, as well as the content of oleic acid (OA) and gamma-linolenic acid (GLA). In addition to the expected increase in transcription levels of genes associated with lipid and TAG synthesis, we observed suppression of lipid degradation and reduced amino acid biosynthesis. This suggested that the deletion of AMPD genes induces the redirection of carbon towards lipid synthesis pathways. Moreover, the pathways related to nitrogen metabolism, including nitrogen assimilation and purine metabolism (especially energy level), were also affected in order to maintain homeostasis. Further analysis discovered that the transcription factors (TFs) related to lipid accumulation were also regulated. This study provides new insights into lipid biosynthesis in M. circinelloides, indicating that the trigger for lipid accumulation is not entirely AMPD-dependent and suggest that there may be additional mechanisms involved in the initiation of lipogenesis., Competing Interests: Declaration of competing interest The authors declare no competing financial interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In the oleaginous fungus Mucor circinelloides, lipid accumulation is regulated by nitrogen metabolism, which is regulated by the areA gene, a member of the GATA zinc finger transporter family and a major regulator for nitrogen metabolism. However, the role of areA in lipid accumulation in this fungus has not been reported. In order to explore the regulatory effect of areA gene on nitrogen metabolism and lipid accumulation in M. circinelloides, we constructed areA gene knockout and overexpression strains. Then, the recombinant strains were cultured and their biochemical indexes were measured. Simultaneously, transcriptomic studies on the recombinant strains were conducted to infer the regulatory mechanism of areA. The results showed that the areA knockout strain accumulated more lipid, which is 42 % higher than the control. While the areA overexpressing strain obtained the higher biomass accumulation (23 g/L) and used up the nitrogen source in the medium earlier than the control strain and knockout strain. Transcriptome data analysis showed that nr and nit-6 genes related to nitrogen metabolism were up-regulated. And the expression levels of key genes acc and aclY were higher in the areA knockout strain than others, which was positively correlated with the increased lipid accumulation. In addition, in knockout strains, protein catabolism tended to provide substrates for the lipid production, and the expression levels of the related genes were also higher than others. These results indicated that the areA gene not only controls the transcription level of genes related to nitrogen metabolism but also affects lipid accumulation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: To assess and compare the in vitro biocompatibility of new resins (Keysplint Soft (Keystone Industries), NextDent Ortho Rigid (3D System), and Freeprint Splint (Detax)) and traditional resins (Orthocryl (Dentaurum)) used for dental splints., Methods: Standardized discs (n = 40) and 1:1, 1:2, and 1:4 extracts of the tested materials were prepared. Human gingival fibroblasts (hGFs) were isolated from gingival tissues. Different biological tests were carried out, including MTT assays to assess cell metabolic activity, cell migration assays, cell cytoskeleton staining, cell apoptosis, generation of intracellular reactive oxygen species (ROS), and scanning electron microscopy (SEM). Statistical analyses were performed using one-way ANOVA and Tukey's post hoc test (p<0.05)., Results: MTT experiments showed that Freeprint Splint significantly reduces the hGF metabolic activity (***p<0.001), whereas SEM analysis showed almost no cells adhered on its surface. Cell migration was significantly lower after exposure to undiluted extracts of Freeprint Splint at 48 and 72 h (***p<0.001). Cell cytoskeleton staining assays showed fewer attached cells in 1:1 and 1:2 dilutions of Freeprint Splint. Annexin-V and 7-AAD staining assays showed that only cells exposed to Keysplint Soft extracts displayed similar cell viability to the control group. Finally, ROS levels detected in undiluted extracts of all resins were significantly enhanced compared to the control group (***p<0.001)., Conclusions: The 3D-printed resins and the conventional dental resin showed a similar biocompatibility, except for Freeprint Splint, which was the most cytotoxic on hGFs., Clinical Significance: 3D printing has been on the rise in recent years and its use in daily clinical practice is expanding over time. Two of the three 3D-printed resins tested in this study performed as well in the cytotoxicity tests as the conventional one, supporting their use, but caution and further testing are required., (Copyright © 2022. Published by Elsevier Ltd.)

Introduction: The aim of this study was to assess the biological properties and mineralization potential of the new Theracal PT (Bisco Inc, Schaumburg, IL) compared with its predecessor Theracal LC (Bisco Inc) and the hydraulic silicate-based cement Biodentine (Septodont, Saint-Maur-des-Fossés, France) on human dental pulp stem cells (hDPSCs) in vitro., Methods: Standardized sample discs were obtained for each material (n = 30) together with 1:1, 1:2, and 1:4 material eluates. Previously characterized hDPSCs were cultured with the different materials in standardized conditions, and the following assays were performed: a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, a wound healing assay, Annexin-V-FITC and 7-AAD staining (BD Biosciences, San Jose, CA), reactive oxygen species production analysis, cell adhesion and morphology evaluation via scanning electron microscopy and immunofluorescence, quantification of the expression of osteo/odontogenic markers via real-time quantitative reverse-transcriptase polymerase chain reaction, and alizarin red S staining. Statistical significance was established at P < .05., Results: All of the tested dilutions of Theracal LC exhibited a significantly higher cytotoxicity and reactive oxygen species production (P < .001) and a lower cell migration rate than the control group (hDPSCs cultured in growth medium without material extracts) at all of the measured time points (P < .001). Both 1:4 Theracal PT and Biodentine-treated hDPSCs exhibited similar levels of cytocompatibility to that of the control group, a significant up-regulation of at least 1 odontogenic marker (Biodentine: dentin sialophosphoprotein (P < .05); Theracal PT: osteonectin and runt-related transcription factor 2 [P < .001]), and a significantly higher mineralized nodule formation (P < .001)., Conclusions: The newly introduced TheraCal PT offers an improved in vitro cytocompatibility and mineralization potential on hDPSCs compared with its predecessor, TheraCal LC, and comparable biological properties to Biodentine., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Melatonin is an endogenous neurohormone with well-reported anti-inflammatory and antioxidant properties, but the direct biological and immunomodulatory effects of melatonin on human dental pulp stem cells (hDPSCs) has not been fully elucidated. The aim of this study was to evaluate the influence of melatonin on the cytocompatibility, proliferation, cell migration, odontogenic differentiation, mineralized nodule formation, and immunomodulatory properties of hDPSCs., Methods: To address the melatonin biological effects on hDPSCs, the cytocompatibility, proliferation, cell migration, odontogenic differentiation, mineralized nodule formation, and immunomodulatory properties of hDPSCs after melatonin treatment were evaluated. The statistical differences were evaluated using 1-way analysis of variance with the Tukey multiple comparison test., Results: We found that melatonin did not alter hDPSC immunophenotype or cell viability, even at the highest concentrations used. However, using intermediate melatonin concentrations (10-300 μmol/L), a significantly higher proliferation rate (P < .05 and P < .01) and migration of hDPSCs (P < .01) were observed. Importantly, melatonin treatment (100 μmol/L) significantly increased the secretion of the anti-inflammatory cytokine transforming growth factor beta (P < .05 and P < .01) and provoked a more robust antiproliferative effect on mitogen-stimulated T cells (P < .05). Finally, and unlike previous results found with mesenchymal stem cells from other sources, melatonin fails to induce or accelerate the spontaneous osteogenic differentiation of hDPSCs., Conclusions: Together, these findings provide key data on the bioactivity of melatonin and its effects on hPDSC biological and immunomodulatory properties., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to evaluate the knowledge of first aid (FA) of primary and pre-school teachers and the parents of children in these education stages., Methods: A questionnaire already used in previous publications was employed and consisted of 4 sections: 1) general information; 2) assessment of FA knowledge; 3) questions about FA, and 4) attitudes about FA. The questionnaire was sent by e-mail in Google Forms format to different education centres of the Autonomous Community of Galicia. The centres were asked to send them to the school staff and parents of the pupils so that they could be completed., Results: A total of 470 questionnaires were analysed (177 teachers; 242 parents and 51 teachers with children). More than half (268, 57%) of the participants stated to have knowledge of FA. In the case of the teachers, a relationship was found between having this information and teaching these contained in the classroom (P=.008). Only 4 participants managed to arrange the basic life support sequence, and none of them correctly answered the questions on cardiopulmonary resuscitation. More than 95% of the sample considered it necessary to include FA in the school curriculum and in the study plans of degrees destined for teacher training., Conclusions: The majority of teachers and parents had training in FA, although none of them responded correctly to the questions related to basic life support. The inclusion of these contents in school curricula would be recommendable, but it requires training the teaching staff beforehand. The inclusion of these contents in university study plans should be a measure to take into account., (Copyright © 2020 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.)

The aim of this work is to investigate the topsoil thickness affected by burning under contrasting soil moisture content (field capacity versus air-dried conditions). A mollic horizon of an Aleppo pine forest was sampled and burned in the laboratory, recording the temperature continuously at the topsoil surface and at soil depths of 1, 2, and 3cm. Changes in soil properties were measured at 0-1, 1-2, 2-3, and 3-4cm. Both the maximum temperature and the charring intensities were significantly lower in wet soils than in air-dried soils up to 3cm in depth. Moreover, soil heating was slower and cooling faster in wet soils as compared to dry soils. Therefore, the heat capacity increase of the soil moistened at field capacity plays a more important role than the thermal conductivity increase on heat transfer on burned soils. Burning did not significantly modify the pH, the carbonate content and the chroma, for either wet or dry soil. Fire caused an immediate and significant decrease in water repellency in the air-dried soil, even at 3cm depth, whereas the wet soil remained hydrophilic throughout its thickness, without being affected by burning. Burning depleted 50% of the soil organic C (OC) content in the air-dried soil and 25% in the wet soil at the upper centimeter, which was blackened. Burning significantly decreased the total N (TN) content only in the dry soil (to one-third of the original value) through the first centimeter of soil depth. Soluble ions, measured by electrical conductivity (EC), increased after burning, although only significantly in the first centimeter of air-dried soils. Below 2cm, burning had no significant effects on the brightness, OC, TN, or EC, for either wet or dry soil., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: To analyze the influence of fins and rescue tube use in a water rescue, assessed by time and distance to salvage position, physiological parameters, and cardiopulmonary resuscitation (CPR)., Methods: Twenty professional lifeguards (10 men, 10 women) conducted 3 tests: a baseline test of 5 minutes of CPR and 2 water rescues, 1 without rescue equipment (NRE), and the other with fins and rescue tube (FRT). They also had to perform 5 minutes of CPR after each rescue. Time and distance of the rescues, physiological parameters (blood lactate concentration and heart rate), and quality of CPR were analyzed., Results: CPR quality worsened by 26 to 28% (P < .001) after rescue. However, there were no differences using FRT. The use of rescue equipment reduced the time (FRT: 216±57 seconds; NRE: 319±127 seconds; P < .001) and distance covered (FRT: 265±52 m; NRE: 326±41 m; P < .001). No differences were found in lactate levels between FRT and NRE just after the rescues, but there were some after 5 minutes of subsequent CPR (FRT: 10.7±2.2 mmol/L; NRE: 12.6±1.8 mmol/L; P < .001). Comparing women with men, we found significant differences in lactate concentrations only in FRT (women: 9.6±1.4 mmol/L; men: 8.1±1.2 mmol/L; P = .031)., Conclusions: The use of fins and rescue tube provides a comprehensive benefit in an aquatic emergency. However, FRT did not have any effect on the quality of the postrescue CPR., (Copyright © 2017 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.)