Pulmonary delivery of fenretinide: A possible adjuvant treatment in COVID-19

At present, there is no vaccine or effective standard treatment for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection (or coronavirus disease-19 (COVID-19)), which frequently leads to lethal pulmonary inflammatory responses. COVID-19 pathology is characterized by extreme inflammation and amplified immune response with activation of a cytokine storm. A subsequent progression to acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) can take place, which is often followed by death. The causes of these strong inflammatory responses in SARS-CoV-2 infection are still unknown. As uncontrolled pulmonary inflammation is likely the main cause of death in SARS-CoV-2 infection, anti-inflammatory therapeutic interventions are particularly important. Fenretinide N-(4-hydroxyphenyl) retinamide is a bioactive molecule characterized by poly-pharmacological properties and a low toxicity profile. Fenretinide is endowed with antitumor, anti-inflammatory, antiviral, and immunomodulating properties other than efficacy in obesity/diabetic pathologies. Its anti-inflammatory and antiviral activities, in particular, could likely have utility in multimodal therapies for the treatment of ALI/ARDS in COVID-19 patients. Moreover, fenretinide administration by pulmonary delivery systems could further increase its therapeutic value by carrying high drug concentrations to the lungs and triggering a rapid onset of activity. This is particularly important in SARS-CoV-2 infection, where only a narrow time window exists for therapeutic intervention

RLZAP: Relative Lempel-Ziv with Adaptive Pointers

Relative Lempel-Ziv (RLZ) is a popular algorithm for compressing databases of genomes from individuals of the same species when fast random access is desired. With Kuruppu et al.'s (SPIRE 2010) original implementation, a reference genome is selected and then the other genomes are greedily parsed into phrases exactly matching substrings of the reference. Deorowicz and Grabowski (Bioinformatics, 2011) pointed out that letting each phrase end with a mismatch character usually gives better compression because many of the differences between individuals' genomes are single-nucleotide substitutions. Ferrada et al. (SPIRE 2014) then pointed out that also using relative pointers and run-length compressing them usually gives even better compression. In this paper we generalize Ferrada et al.'s idea to handle well also short insertions, deletions and multi-character substitutions. We show experimentally that our generalization achieves better compression than Ferrada et al.'s implementation with comparable random-access times

Combined use of x-ray fluorescence microscopy, phase contrast imaging for high resolution quantitative iron mapping in inflamed cells

X-ray fluorescence microscopy (XRFM) is a powerful technique to detect and localize elements in cells. To derive information useful for biology and medicine, it is essential not only to localize, but also to map quantitatively the element concentration. Here we applied quantitative XRFM to iron in phagocytic cells. Iron, a primary component of living cells, can become toxic when present in excess. In human fluids, free iron is maintained at 10-18 M concentration thanks to iron binding proteins as lactoferrin (Lf). The iron homeostasis, involving the physiological ratio of iron between tissues/secretions and blood, is strictly regulated by ferroportin, the sole protein able to export iron from cells to blood. Inflammatory processes induced by lipopolysaccharide (LPS) or bacterial pathoge inhibit ferroportin synthesis in epithelial and phagocytic cells thus hindering iron export, increasing intracellular iron and bacterial multiplication. In this respect, Lf is emerging as an important regulator of both iron and inflammatory homeostasis. Here we studied phagocytic cells inflamed by bacterial LPS and untreated or treated with milk derived bovine Lf. Quantitative mapping of iron concentration and mass fraction at high spatial resolution is obtained combining X-ray fluorescence microscopy, atomic force microscopy and synchrotron phase contrast imaging

Assessment and imaging of intracellular magnesium in saos-2 osteosarcoma cells and its role in proliferation

Magnesium is an essential nutrient involved in many important processes in living organ-isms, including protein synthesis, cellular energy production and storage, cell growth and nucleic acid synthesis. In this study, we analysed the effect of magnesium deficiency on the proliferation of SaOS-2 osteosarcoma cells. When quiescent magnesium-starved cells were induced to proliferate by serum addition, the magnesium content was 2–3 times lower in cells maintained in a medium without magnesium compared with cells growing in the presence of the ion. Magnesium depletion inhibited cell cycle progression and caused the inhibition of cell proliferation, which was associated with mTOR hypophosphorylation at Serine 2448. In order to map the intracellular magnesium distribution, an analytical approach using synchrotron-based X-ray techniques was applied. When cell growth was stimulated, magnesium was mainly localized near the plasma membrane in cells maintained in a medium without magnesium. In non-proliferating cells growing in the presence of the ion, high concentration areas inside the cell were observed. These results support the role of magnesium in the control of cell proliferation, suggesting that mTOR may represent an important target for the antiproliferative effect of magnesium. Selective control of magnesium availability could be a useful strategy for inhibiting osteosarcoma cell growth

Analysis of intracellular magnesium and mineral depositions during osteogenic commitment of 3d cultured saos2 cells

In this study, we explore the behaviour of intracellular magnesium during bone phenotype modulation in a 3D cell model built to mimic osteogenesis. In addition, we measured the amount of magnesium in the mineral depositions generated during osteogenic induction. A two-fold increase of intracellular magnesium content was found, both at three and seven days from the induction of differentiation. By X-ray microscopy, we characterized the morphology and chemical composition of the mineral depositions secreted by 3D cultured differentiated cells finding a marked co-localization of Mg with P at seven days of differentiation. This is the first experimental evidence on the presence of Mg in the mineral depositions generated during biomineralization, suggesting that Mg incorporation occurs during the bone forming process. In conclusion, this study on the one hand attests to an evident involvement of Mg in the process of cell differentiation, and, on the other hand, indicates that its multifaceted role needs further investigation

Relative Lempel-Ziv Compression of Suffix Arrays

We show that a combination of differential encoding, random sampling, and relative Lempel-Ziv (RLZ) parsing is effective for compressing suffix arrays, while simultaneously allowing very fast decompression of arbitrary suffix array intervals, facilitating pattern matching. The resulting text index, while somewhat larger (5-10x) than the recent r-index of Gagie, Navarro, and Prezza (Proc. SODA ’18)—still provides significant compression, and allows pattern location queries to be answered more than two orders of magnitude faster in practice.Peer reviewe

PO-357 SREBP1 drives cell-autonomous cytoskeletal changes by KRT80 remodelling during ERα breast cancer progression

Introduction Approximately 30% of oestrogen receptor α positive (ERα) breast cancer patients progress to invasive metastatic disease despite adjuvant treatment with targeted endocrine therapies. The relationship between acquisition of drug resistance and invasive potential is poorly understood. Currently, invasive behaviour is thought to be driven mainly by epithelial to mesenchymal transition. Material and methods MCF7 cell line and derived resistant clones were used for this study. MCF7 Tamoxifen Resistant (MCF7TR) and LTED (Long Term Oestrogen Deprivation) were derived from MCF7 upon one-year Tamoxifen or oestrogen deprivation, respectively. LTED combination treatments were also used (LTEDT and LTEDF). Additionally, we used T47D and T47D-LTED. Stable cell lines were generated for both KRT80 over-expression and knockdown. 3D organoids invasion assay, immunofluorescence, confocal microscopy, RNA-seq, ChIP-seq, RT-qPCR and Western blot were performed. Seventy-five human breast specimens and ten metastatic lymph nodes were selected with the approval of Imperial College Healthcare NHS Trust Tissue Bank. Twenty women with suspected breast cancer were prospectively recruited and radiological exam using shear wave ultrasound was used to determine tissue stiffness in the normal and peri-tumoral stroma, and suspected lesion. Results and discussions In this study, we show that cells that acquire resistance to aromatase inhibitors (AI) undergo active cytoskeleton re-organisation via Keratin 80 (KRT80) and F-Actin remodelling. These features directly drive the invasive phenotype. Mechanistically, we show that this process is driven by epigenetic reprogramming at the type II keratin locus (chromosome 12) leading to Keratin 80 (KRT80) up-regulation. Reprogramming is dependent on de novo SREBP1 binding to a single enhancer that is activated upon chronic AI treatment. AI-treated patients show KRT80 cytoskeletal re-organisation and an increased number of KRT80 positive cells at relapse. We find that KRT80 activation and redeployment leads to increased F-actin deposition and focal adhesion. Additionally, we show that KRT80 manipulation directly contributes to changes in cellular stiffness and invasive potential. In agreement, shear-wave elasticity imaging of prospective patients show that KRT80 levels correlate with stiffer tumours in vivo. Conclusion Collectively, our data uncover an unexpected and potentially targetable link between epigenetic reprogramming and cytoskeletal changes promoting cell invasion

Production of a xylanase by Trichoderma harzianum (Hypocrea lixii) in solid-state fermentation and its recovery by an aqueous two-phase system

Production of xylanase enzyme by fungi strains has gained interest in the recent years due to its high productivity, high catalytic power, as well as its potential applications in different areas such as feed, food, textile, and biofuel industries. The conventional methodologies, to produce enzymes, involve complex apparatus and chemical solvents and are associated with high costs and low- yield recovery. To obtain the high-yield recovery of the enzymes, modern enzyme extraction methods are taken into account. Aqueous two-phase systems (ATPS) are an alternative separative methodology for the purification and recovery of the enzymes and other biomolecules. The advantages of ATPS are easy scale-up and extraction, volume reduction, and rapid separation. The objective of this study was to produce Trichoderma harzianum xylanase by solid-state fermentation (SSF) using corn cobs as a support/substrate and employing ATPS for its partial recovery. In this study, the results showed the ability of a microorganism to grow on the corn cobs and to produce the xylanase enzyme. Xylanolytic activity reached 7.85 U/g of corn cobs. The enzyme was efficiently concentrated by ATPS. In addition, a high purification factor (10-fold) and considerable enzyme recovery (%ER) (84%) percentage were obtained