MicroRNA-Mediated Regulation of the Virus Cycle and Pathogenesis in the SARS-CoV-2 Disease

In the last few years, microRNA-mediated regulation has been shown to be important in viral infections. In fact, viral microRNAs can alter cell physiology and act on the immune system; moreover, cellular microRNAs can regulate the virus cycle, influencing positively or negatively viral replication. Accordingly, microRNAs can represent diagnostic and prognostic biomarkers of infectious processes and a promising approach for designing targeted therapies. In the past 18 months, the COVID-19 infection from SARS-CoV-2 has engaged many researchers in the search for diagnostic and prognostic markers and the development of therapies. Although some research suggests that the SARS-CoV-2 genome can produce microRNAs and that host microRNAs may be involved in the cellular response to the virus, to date, not enough evidence has been provided. In this paper, using a focused bioinformatic approach exploring the SARS-CoV-2 genome, we propose that SARS-CoV-2 is able to produce microRNAs sharing a strong sequence homology with the human ones and also that human microRNAs may target viral RNA regulating the virus life cycle inside human cells. Interestingly, all viral miRNA sequences and some human miRNA target sites are conserved in more recent SARS-CoV-2 variants of concern (VOCs). Even if experimental evidence will be needed, in silico analysis represents a valuable source of information useful to understand the sophisticated molecular mechanisms of disease and to sustain biomedical applications.     

Influence of Chemical Reactions in Magnesia-Graphite Refractories: I, Effects on Texture and High-Temperature Mechanical Properties

Four formulations of magnesia-graphite-aluminum metal (antioxidant) bricks were prepared from the same raw materials, using the standard commercial practices. Chemical analysis and determination of room-temperature modulus of rupture and Young's modulus, as well as a complete microstructural characterization of the as-received materials, were performed. For high-temperature modulus-of-rupture and Young's modulus data, test samples of the four brick compositions were heated to 1000°, 1200°, and 1450°C in flowing argon (<1000 ppm oxygen at 1000°C) and then loaded mechanically in flexure. Modulus-of-elasticity values ranged from 3.7 to 16.2 GPa and reflected strong effects of aluminum-metal concentration and treatment temperature. Young's modulus evolution with temperature was determined by the evolution of the microstructure in the bulk of the specimens. Modulus-of-rupture values ranged from 6 to 21 MPa, and their evolution with temperature was determined by the evolution of the microstructure in the bulk of the specimens at the lower testing temperatures ( T lessthan equal to 1200°C) and by phase assemblages in the surface regions of the specimens-essentially by the presence of the dense MgO zone-at 1450°C.     

Divergent Detonation Wave Processes in PBX Based on RDX

In order to characterize the initial phase of the divergent detonation wave in PBX, a hemispheric explosive sample was initiated by a long cylindrical charge of the same explosive. The tested PBX is composed of 85 wt% of RDX and 15 wt% of binder based on HTPB. This PBX‐RDX presents an effective density of 1.57 g/cm³, and a detonation velocity of 7.90 mm/μs.     

Wnt/β-Catenin Signaling Contributes to Paclitaxel Resistance in Bladder Cancer Cells with Cancer Stem Cell-Like Properties

The Wnt/β-catenin pathway plays an important role in tumor progression and chemotherapy resistance and seems to be essential for the maintenance of cancer stem cells (CSC) in several tumor types. However, the interplay of these factors has not been fully addressed in bladder cancer. Here, our goal was to analyze the role of the Wnt/β-catenin pathway in paclitaxel resistance and to study the therapeutic efficacy of its inhibition in bladder cancer cells, as well as to determine its influence in the maintenance of the CSC-like phenotype in bladder cancer. Our results show that paclitaxel-resistant HT1197 cells have hyperactivation of the Wnt/β-catenin pathway and increased CSC-like properties compared with paclitaxel-sensitive 5637 cells. Paclitaxel sensitivity diminishes in 5637 cells after β-catenin overexpression or when they are grown as tumorspheres, enriched for the CSC-like phenotype. Additionally, downregulation of β-catenin or inhibition with XAV939 sensitizes HT1197 cells to paclitaxel. Moreover, a subset of muscle-invasive bladder carcinomas shows aberrant expression of β-catenin that associates with positive expression of the CSC marker ALDH1A1. In conclusion, we demonstrate that Wnt/β-catenin signaling contributes to paclitaxel resistance in bladder cancer cells with CSC-like properties.     

In vitro protein digestibility and mineral availability of green beans (Phaseolus vulgarisL) as influenced by variety and pod size

Three varieties of green beans (Cleo, Strike and Sentry) were harvested and sorted into four fractions according to pod size (diameter <7 mm; 7–8·5 mm; 8·6–10 mm and >10 mm). Ash content and dietary fibre increased significantly as pod size increased mainly in Cleo and Strike beans. Strike showed the highest fibre content (378·0 g kg⁻¹) but the lowest carbohydrate (364·6 g kg⁻¹) and ash (68·4 g kg⁻¹) values. Mean values for Fe and Mg content were higher in Cleo beans (70·9 and 27·1 mg kg⁻¹, respectively), Zn, Cu and Mg were higher in Strike beans (48·7 mg kg⁻¹, 22·4 mg kg⁻¹ and 3·15 g kg⁻¹, respectively) while Na and Ca values were maximum in Sentry (459·1 mg kg⁻¹ and 7·11 g kg⁻¹, respectively). Trypsin inhibitor was negatively related to in vitro protein digestibility but no relationship was found between this last parameter and phytic acid content. This antinutrient, together with dietary fibre, and a negative influence on in vitro mineral dialysability of green beans. © 1998 SCI     

Intrinsic Angiogenic Potential and Migration Capacity of Human Mesenchymal Stromal Cells Derived from Menstrual Blood and Bone Marrow

Several therapies are being developed to increase blood circulation in ischemic tissues. Despite bone marrow-derived mesenchymal stromal cells (bmMSC) are still the most studied, an interesting and less invasive MSC source is the menstrual blood, which has shown great angiogenic capabilities. Therefore, the aim of this study was to evaluate the angiogenic properties of menstrual blood-derived mesenchymal stromal cells (mbMSC) in vitro and in vivo and compared to bmMSC. MSC’s intrinsic angiogenic capacity was assessed by sprouting and migration assays. mbMSC presented higher invasion and longer sprouts in 3D culture. Additionally, both MSC-spheroids showed cells expressing CD31. mbMSC and bmMSC were able to migrate after scratch wound in vitro, nonetheless, only mbMSC demonstrated ability to engraft in the chick embryo, migrating to perivascular, perineural, and chondrogenic regions. In order to study the paracrine effects, mbMSC and bmMSC conditioned mediums were capable of stimulating HUVEC’s tube-like formation and migration. Both cells expressed VEGF-A and FGF2. Meanwhile, PDGF-B was expressed exclusively in mbMSC. Our results indicated that mbMSC and bmMSC presented a promising angiogenic potential. However, mbMSC seems to have additional advantages since it can be obtained by non-invasive procedure and expresses PDGF-B, an important molecule for vascular formation and remodeling.     

Correction to: Consumption of non-nutritive sweeteners by pre-schoolers of the food and environment Chilean cohort (FECHIC) before the implementation of the Chilean food labelling and advertising law

Nutritional treatment is one of the most important components of multidisciplinary anti-cancer therapy. Home enteral nutrition is considered as a safe procedure, however, it may be associated with the risk of side effects, such as nausea, vomiting, abdominal pain, and diarrhoea. It is uncertain whether diarrhoea is the result of the enteral formula administration or gut dysbiosis. One of the methods which may be used to alter the composition of gut microbiota is the administration of a probiotic strain. Lactobacillus plantarum 299v ingestion was found to diminish the adverse events of irritable bowel syndrome and Clostridium difficile infection - entities that share the symptoms with enteral nutrition side effects. Therefore, the primary aim of this study is to determine the effect of Lactobacillus plantarum 299v on prevention of weight loss of cancer patients receiving home enteral nutrition. The secondary aims are to evaluate the role of this probiotic strain in the improvement of nutritional status, enteral nutrition tolerance, and patients’ quality of life. Forty patients with cancer receiving home enteral nutrition will be enrolled in this clinical trial and randomized to receive one capsule of Lactobacillus plantarum 299v (Sanprobi IBS®) twice a day or placebo for 12 weeks in a double-blind manner. Laboratory tests (the level of albumin, total protein, transferrin, and total lymphocyte count), anthropometric parameters (body mass, the content of fat mass, muscle mass, and total body water), Nutritional Risk Screening (NRS 2002), enteral nutrition tolerance as well as quality of life will be measured. Measurements will be obtained at the baseline and after 4 and 12 weeks of treatment. The adverse events observed during administration of enteral nutrition have an negative impact on enteral formula tolerance and as a consequence patients’ quality of life. The previous studies have demonstrated that probiotics may reduce the gastrointestinal symptoms related to enteral nutrition. Thus, administration of Lactobacillus plantarum 299v may be effective in improvement of nutritional status, enteral nutrition tolerance, and quality of life of cancer patients receiving home enteral nutrition. ClinicalTrials.gov Identifier: NCT03940768 .     

Differential lipid damage in various muscle zones of frozen hake (Merluccius merluccius)

 A comparison of the lipid damage produced in different hake zones was carried out during frozen storage at –11 and –18  °C. Three light muscle zones and the dark muscle were considered. Lipid oxidation [conjugated dienes; thiobarbituric acid index (TBA-i); fluorescence formation] and hydrolysis (free fatty acids, FFA) were determined. The most predominant lipid damage in all zones was hydrolysis, at the end of storage reaching values of about 40% (for the light muscle zones) and 12% (for the dark muscle) of the total lipids at –11  °C. Significant (P<0.05) correlation value (r=0.67–0.85) relationships between the frozen storage time and the FFA content were obtained for the four muscle zones at both temperatures. A comparison of the regression lines slopes in the different zones showed that a lower (P<0.05) lipolitic activity was produced in the dark muscle compared to the three light zones at both temperatures. A low lipid oxidation development was produced in the three light muscle parts, so that no significant differences between them could be assessed. However, the dark muscle showed a higher oxidation development (TBA-i and fluorescence formation) as a result of a higher lipid content and the presence of prooxidant constituents.     

Synthesis and characterization of β-cyclodextrin inclusion complexes of thymol and thyme oil for antimicrobial delivery applications

Microencapsulation with β-cyclodextrin (β-CD) as a delivery platform offers a promising application for natural antimicrobial delivery for food safety. Hence, this study aimed to characterize inclusion complexes of thymol and thyme essential oil with β-CD and their resulting antimicrobial activities. Inclusion complexes were prepared by kneading (KN) and freeze-drying (FD) methods. The entrapment efficiencies ranged from 71 to 83 g/100 g with higher (P < 0.05) values for thymol and FD particles. All particles showed irregular shapes and sharp edges with significant differences in size distribution and strong tendency to agglomerate. FD produced higher (P < 0.05) particle sizes than KN method. Differential Scanning Calorimetry (DSC) analysis confirmed inclusion complexes formation between β-CD and both compounds. Phase solubility tests indicated B_S-type complexes formation between thymol and β-CD. All compounds effectively inhibited bacterial growth within the concentration range tested. Free thyme oil showed higher (P < 0.05) antimicrobial activity than thymol, and FD β-CD inclusion complexes were able to inhibit Escherichia coli K12 at lower (P < 0.05) active compound concentrations than corresponding free oils. Antimicrobial activities of β-CD inclusion complexes against total viable counts in pork meat system throughout storage were observed. The FD method showed to be the best encapsulation method with enhanced antimicrobial activity for both compounds.