Dual Stimuli Responsive Gelatin‐CNT Hybrid Films as a Versatile Tool for the Delivery of Anionic Drugs

Hybrid hydrogel films able to modulate the release of anionic species, ketoprofen (Ket) and bovine serum albumin (BSA), as a function of their molecular size are prepared by UV‐induced polymerization of methacrylated gelatin in the presence of oxidized multiwalled carbon nanotubes (MWNT_COOH). The dual‐stimuli responsive composites can modulate the release in response to the variation of temperature and the application of an external voltage. Drug release profiles, analyzed by mathematical models, show that different temperatures (25 and 45 °C) and applied voltages (0 and 36 V) have a different effect on the release of the two therapeutics. Ket release is enhanced at 45 °C (77% vs 22% at 25 °C) with the maximum value recorded when 36 V is applied (94%). An increase in the amount of released BSA is recorded at 45 °C (96% vs 50% at 25 °C), while the application of the external voltage reduces this value (39%).

     

Aminolysis of Styrene Oxide Over Heterogeneous Acidic Catalysts

Silica alumina and silica zirconia mixed oxides are shown to be effective and regioselective catalysts for the aminolysis of styrene oxide under very mild experimental conditions, giving the corresponding primary ??-amino-alcohol in good to excellent yield.     

In Vitro SARS-CoV-2 Infection of Microvascular Endothelial Cells: Effect on Pro-Inflammatory Cytokine and Chemokine Release

In the novel pandemic of Coronavirus Disease 2019, high levels of pro-inflammatory cytokines lead to endothelial activation and dysfunction, promoting a pro-coagulative state, thrombotic events, and microvasculature injuries. The aim of the present work was to investigate the effect of SARS-CoV-2 on pro-inflammatory cytokines, tissue factor, and chemokine release, with Human Microvascular Endothelial Cells (HMEC-1). ACE2 receptor expression was evaluated by western blot analysis. SARS-CoV-2 infection was assessed by one-step RT-PCR until 7 days post-infection (p.i.), and by Transmission Electron Microscopy (TEM). IL-6, TNF-α, IL-8, IFN-α, and hTF mRNA expression levels were detected by RT-PCR, while cytokine release was evaluated by ELISA. HMEC-1 expressed ACE2 receptor and SARS-CoV-2 infection showed a constant viral load. TEM analysis showed virions localized in the cytoplasm. Expression of IL-6 at 24 h and IFN-α mRNA at 24 h and 48 h p.i. was higher in infected than uninfected HMEC-1 (p < 0.05). IL-6 levels were significantly higher in supernatants from infected HMEC-1 (p < 0.001) at 24 h, 48 h, and 72 h p.i., while IL-8 levels were significantly lower at 24 h p.i. (p < 0.001). These data indicate that in vitro microvascular endothelial cells are susceptible to SARS-CoV-2 infection but slightly contribute to viral amplification. However, SARS-CoV-2 infection might trigger the increase of pro-inflammatory mediators.     

Exploring Mitochondrial Localization of SARS-CoV-2 RNA by Padlock Assay: A Pilot Study in Human Placenta

The ongoing COVID-19 pandemic dictated new priorities in biomedicine research. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, is a single-stranded positive-sense RNA virus. In this pilot study, we optimized our padlock assay to visualize genomic and subgenomic regions using formalin-fixed paraffin-embedded placental samples obtained from a confirmed case of COVID-19. SARS-CoV-2 RNA was localized in trophoblastic cells. We also checked the presence of the virion by immunolocalization of its glycoprotein spike. In addition, we imaged mitochondria of placental villi keeping in mind that the mitochondrion has been suggested as a potential residence of the SARS-CoV-2 genome. We observed a substantial overlapping of SARS-CoV-2 RNA and mitochondria in trophoblastic cells. This intriguing linkage correlated with an aberrant mitochondrial network. Overall, to the best of our knowledge, this is the first study that provides evidence of colocalization of the SARS-CoV-2 genome and mitochondria in SARS-CoV-2 infected tissue. These findings also support the notion that SARS-CoV-2 infection can reprogram mitochondrial activity in the highly specialized maternal–fetal interface.     

Characterization of Chromosomal Breakpoints in 12 Cases with 8p Rearrangements Defines a Continuum of Fragility of the Region

Improvements in microarray-based comparative genomic hybridization technology have allowed for high-resolution detection of genome wide copy number alterations, leading to a better definition of rearrangements and supporting the study of pathogenesis mechanisms. In this study, we focused our attention on chromosome 8p. We report 12 cases of 8p rearrangements, analyzed by molecular karyotype, evidencing a continuum of fragility that involves the entire short arm. The breakpoints seem more concentrated in three intervals: one at the telomeric end, the others at 8p23.1, close to the beta-defensin gene cluster and olfactory receptor low-copy repeats. Hypothetical mechanisms for all cases are described. Our data extend the cohort of published patients with 8p aberrations and highlight the need to pay special attention to these sequences due to the risk of formation of new chromosomal aberrations with pathological effects.     

Second Cancer Onset in Myeloproliferative Neoplasms: What,When, Why?

The risk of developing a solid cancer is a major issue arising in the disease course of a myeloproliferative neoplasm (MPN). Although the connection between the two diseases has been widely described, the backstage of this complex scenario has still to be explored. Several cellular and molecular mechanisms have been suggested to link the two tumors. Sometimes the MPN is considered to trigger a second cancer but at other times both diseases seem to depend on the same source. Increasing knowledge in recent years has revealed emerging pathways, supporting older, more consolidated theories, but there are still many unresolved issues. Our work aims to present the biological face of the complex clinical scenario in MPN patients developing a second cancer, focusing on the main cellular and molecular pathways linking the two diseases.     

Exposure to b-LED Light While Exerting Antimicrobial Activity on Gram-Negative and -Positive Bacteria Promotes Transient EMT-like Changes and Growth Arrest in Keratinocytes

While blue LED (b-LED) light is increasingly being studied for its cytotoxic activity towards bacteria in therapy of skin-related infections, its effects on eukaryotic cells plasticity are less well characterized. Moreover, since different protocols are often used, comparing the effect of b-LED towards both microorganisms and epithelial surfaces may be difficult. The aim of this study was to analyze, in the same experimental setting, both the bactericidal activity and the effects on human keratinocytes. Exposure to b-LED induced an intense cytocidal activity against Gram-positive (i.e, Staphylococcus aureus) and Gram-negative (i.e., Pseudomonas aeruginosa) bacteria associated with catheter-related infections. Treatment with b-LED of a human keratinocyte cell line induced a transient cell cycle arrest. At the molecular level, exposure to b-LED induced a transient downregulation of Cyclin D1 and an upregulation of p21, but not signs of apoptosis. Interestingly, a transient induction of phosphor-histone γ-H2Ax, which is associated with genotoxic damages, was observed. At the same time, keratinocytes underwent a transient epithelial to mesenchymal transition (EMT)-like phenotype, characterized by E-cadherin downregulation and SNAIL/SLUG induction. As a functional readout of EMT induction, a scratch assay was performed. Surprisingly, b-LED treatment provoked a delay in the scratch closure. In conclusion, we demonstrated that b-LED microbicidal activity is associated with complex responses in keratinocytes that certainly deserve further analysis.     

Flavin‐grafted poly(vinyl alcohol): Preparation and properties

An NAD(P)H oxidase‐like activity was found in semisynthetic flavoadducts, prepared from an aldehyde derivative of riboflavin and commercial poly(vinylalcohol) (PVA), previously grafted with aminopropyl side chains. Both water‐soluble and water‐insoluble beaded preparations were obtained. The products showed a noticeable NAD(P)H oxidase‐like activity, converting the nucleotide substrate to its oxidized counterpart NAD(P)⁺ at the expense of molecular oxygen, the latter being reduced to hydrogen peroxide. In contrast to some “true” β‐NAD(P)H oxidases, the PVA adducts do not require the presence of additional flavin adenine dinucleotide (FAD) to work; some properties of the flavoadducts were studied that make these flavoadducts good candidates for technological applications. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2471–2477, 2002     

Truncation versus mapping in the spectral approximation to the Korteweg-De Vries equation

We propose two different approaches to the numerical solution of the initial boundary value problem for the Korteweg-De Vries equation; the former is based on the truncation of the domain, the latter on the reduction of the real axis to a bounded interval by a suitable mapping technique. In both cases we consider spectral Chebyshev collocation methods for the space discretization and finite difference schemes for advancing in time. Both single and multi-domain approaches are discussed. We report numerical experiments showing the stability and convergence properties of the methods