Publications by authors named "Silvana Rocco"

Breast cancer (BC) remains a significant global health concern, with neoadjuvant chemotherapy (NACT) offering preoperative benefits like tumor downstaging and treatment response assessment. However, identifying factors influencing post-NACT treatment response and survival outcomes is challenging. Metabolomic approaches offer promising insights into understanding these outcomes.

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Article Synopsis
  • - Propolis, a complex resin produced by bees, varies in composition based on the plants the bees visit, and red Brazilian propolis shows promising antimicrobial properties that need further investigation.
  • - This study aimed to refine a method to efficiently extract and isolate beneficial compounds from red propolis using counter-current chromatography and preparative HPLC, addressing issues like wax removal that can clog equipment.
  • - The researchers successfully isolated three key compounds linked to red propolis's therapeutic effects, identifying them as retusapurpurin A, 3()-7-O-methylvestitol, and xanthochymol/isoxanthochymol, which will aid in future biological testing and serve as standards in chromatography.
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Concerns over Bisphenol A (BPA) and its substitute, Bisphenol S (BPS), have led to innovative exploration due to potential adverse health effects. BPS, replacing BPA in some regions to avoid toxic impacts, remains insufficiently studied. Besides this, the organ-on-a-chip technology emerges as a transformative solution in drug discovery and chemiclas toxicity testing, minimizing costs and aligning with ethical standards by reducing reliance on animal models, by integrating diverse tissues and dynamic cell environments enhances precision in predicting organ function.

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To synthesize HER2 aptamer-conjugated iron oxide nanoparticles with a coating of poly(2-(dimethylamino) ethyl methacrylate)-poly(2-methacryloyloxyethylphosphorylcholine) block copolymer (IONPPPs). Characterization covered molecular structure, chemical composition, thermal stability, magnetic characteristics, aptamer interaction, crystalline nature and microscopic features. Subsequent investigations focused on IONPPPs for cancer cell identification.

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Metformin is the most prescribed drug for DM2, but its site and mechanism of action are still not well established. Here, we investigated the effects of metformin on basolateral intestinal glucose uptake (BIGU), and its consequences on hepatic glucose production (HGP). In diabetic patients and mice, the primary site of metformin action was the gut, increasing BIGU, evaluated through PET-CT.

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The nucleocapsid (N) protein plays critical roles in coronavirus genome transcription and packaging, representing a key target for the development of novel antivirals, and for which structural information on ligand binding is scarce. We used a novel fluorescence polarization assay to identify small molecules that disrupt the binding of the N protein to a target RNA derived from the SARS-CoV-2 genome packaging signal. Several phenolic compounds, including L-chicoric acid (CA), were identified as high-affinity N-protein ligands.

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Neoadjuvant chemotherapy (NACT) is offered to patients with operable or inoperable breast cancer (BC) to downstage the disease. Clinical responses to NACT may vary depending on a few known clinical and biological features, but the diversity of responses to NACT is not fully understood. In this study, 80 women had their metabolite profiles of pre-treatment sera analyzed for potential NACT response biomarker candidates in combination with immunohistochemical parameters using Nuclear Magnetic Resonance (NMR).

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The ongoing COVID-19 pandemic caused a significant loss of human lives and a worldwide decline in quality of life. Treatment of COVID-19 patients is challenging, and specific treatments to reduce COVID-19 aggravation and mortality are still necessary. Here, we describe the discovery of a novel class of epiandrosterone steroidal compounds with cationic amphiphilic properties that present antiviral activity against SARS-CoV-2 in the low micromolar range.

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Ellipticine was synthesized in six steps and 20% global yield starting from the readily available 2,5-dimethoxy isoquinoline. Unprecedented regioselective control of the nucleophilic attack on the isoquinoline-5,8-dione is first described. Investigation of the possible pathways of this transformation through density functional theory calculations reveals unexpected -oxide assistance in cascade tautomerizations, which was crucial for directing the nucleophilic attack and hastening the overall process.

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Wound healing materials to prevent blood loss are crucial during emergency medical treatment because uncontrolled bleeding can lead to patient death. Herein, bioabsorbable fibrous architectures of thrombin-loaded poly(ethylene oxide)-PEO/thrombin-are conceptualized and accomplished electrospinning for faster wound clotting. Membranes with average fiber diameters ranging from 188 to 264 nm are achieved, where the active thrombin is entrapped within the nanofibers.

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Xyloglucans are highly substituted and recalcitrant polysaccharides found in the primary cell walls of vascular plants, acting as a barrier against pathogens. Here, we reveal that the diverse and economically relevant Xanthomonas bacteria are endowed with a xyloglucan depolymerization machinery that is linked to pathogenesis. Using the citrus canker pathogen as a model organism, we show that this system encompasses distinctive glycoside hydrolases, a modular xyloglucan acetylesterase and specific membrane transporters, demonstrating that plant-associated bacteria employ distinct molecular strategies from commensal gut bacteria to cope with xyloglucans.

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The recently introduced microphysiological systems (MPS) cultivating human organoids are expected to perform better than animals in the preclinical tests phase of drug developing process because they are genetically human and recapitulate the interplay among tissues. In this study, the human intestinal barrier (emulated by a co-culture of Caco-2 and HT-29 cells) and the liver equivalent (emulated by spheroids made of differentiated HepaRG cells and human hepatic stellate cells) were integrated into a two-organ chip (2-OC) microfluidic device to assess some acetaminophen (APAP) pharmacokinetic (PK) and toxicological properties. The MPS had three assemblies: Intestine only 2-OC, Liver only 2-OC, and Intestine/Liver 2-OC with the same media perfusing both organoids.

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Article Synopsis
  • * The research presents a new drug discovery approach focused on MtDHFR, identifying novel chemical structures that have not been previously considered for targeting this enzyme.
  • * Through structure-activity relationship (SAR) strategies, the study has developed compounds that bind effectively to MtDHFR, revealing unique binding properties that could help in creating new inhibitors for treating tuberculosis.
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The liver is responsible for many metabolic, endocrine and exocrine functions. Approximately 2 million deaths per year are associated with liver failure. Modern 3D bioprinting technologies allied with autologous induced pluripotent stem cells (iPS)-derived grafts could represent a relevant tissue engineering approach to treat end stage liver disease patients.

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Many types of cancers have a well-established dependence on glutamine metabolism to support survival and growth, a process linked to glutaminase 1 (GLS) isoforms. Conversely, GLS2 variants often have tumor-suppressing activity. Triple-negative (TN) breast cancer (testing negative for estrogen, progesterone, and Her2 receptors) has elevated GLS protein levels and reportedly depends on exogenous glutamine and GLS activity for survival.

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Poly(A) tail shortening is a critical step in messenger RNA (mRNA) decay and control of gene expression. The carbon catabolite repressor 4 (CCR4)-associated factor 1 (CAF1) component of the CCR4-NOT deadenylase complex plays an essential role in mRNA deadenylation in most eukaryotes. However, while CAF1 has been extensively investigated in yeast and animals, its role in plants remains largely unknown.

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Salicylic acid (SA) and its methyl ester, methyl salicylate (MeSA) are well known inducers of local and systemic plant defense responses, respectively. MeSA is a major mediator of systemic acquired resistance (SAR) and its conversion back into SA is thought to be required for SAR. In many plant species, conversion of MeSA into SA is mediated by MeSA esterases of the SABP2 family.

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This study describes the characterization of pharmacokinetic (PK) properties of acetaminophen (APAP) in the Two-Organ-Chip platform (2-OC), a two-chamber device able to cultivate 3D tissues under flow. The APAP intestinal absorption and hepatic metabolism were emulated by human intestine and liver equivalents respectively. The intestinal barrier was produced using Caco-2 and HT-29 cells.

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Background: Moniliophthora perniciosa (Stahel) Aime & Phillips-Mora is the causal agent of witches' broom disease (WBD) of cocoa (Theobroma cacao L.) and a threat to the chocolate industry. The membrane-bound enzyme alternative oxidase (AOX) is critical for M.

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Adenosine Kinase (ADK) regulates the cellular levels of adenosine (ADO) by fine-tuning its metabolic clearance. The transfer of γ-phosphate from ATP to ADO by ADK involves regulation by the substrates and products, as well as by Mg and inorganic phosphate. Here we present new crystal structures of mouse ADK (mADK) binary (mADK:ADO; 1.

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Nucleoside diphosphate kinases (NDKs) are key enzymes in the purine-salvage pathway of trypanosomatids and have been associated with the maintenance of host-cell integrity for the benefit of the parasite, being potential targets for rational drug discovery and design. The NDK from Leishmania major (LmNDK) and mutants were expressed and purified to homogeneity. Thermal shift assays were employed to identify potential inhibitors for LmNDK.

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