132 research outputs found
Efficient Triazine Derivatives for Collagenous Materials Stabilization
Nowadays, the need to reduce plastic waste and scantly biodegradable fossil-based products
is of great importance. The use of leather as an alternative to synthetic materials is gaining
renewed interest, but it is fundamental that any alternative to plastic-based materials should not generate an additional environmental burden. In the present work, a simple protocol for collagen stabilization mediated by 2-chloro-4,6-diethoxy-1,3,5-triazine (CDET) and a tert-amine has been described. Different tert-amines were tested in combination with CDET in a standard amidation reaction between 2-phenylethylamine and benzoic acid. Best performing condensation systems have been further tested for the cross-linking of both collagen powder and calf hides. The best results were achieved with CDET/NMM giving high-quality leather with improved environmental performances.Nowadays, the need to reduce plastic waste and scantly biodegradable fossil-based products is of great importance. The use of leather as an alternative to synthetic materials is gaining renewed interest, but it is fundamental that any alternative to plastic-based materials should not generate an additional environmental burden. In the present work, a simple protocol for collagen stabilization mediated by 2-chloro-4,6-diethoxy-1,3,5-triazine (CDET) and a tert-amine has been described. Different tert-amines were tested in combination with CDET in a standard amidation reaction between 2-phenylethylamine and benzoic acid. Best performing condensation systems have been further tested for the cross-linking of both collagen powder and calf hides. The best results were achieved with CDET/NMM giving high-quality leather with improved environmental performances
The F1Fo-ATPase inhibitor protein IF1 in pathophysiology
The endogenous inhibitor of ATP synthase is a protein of about 10 kDa, known as IF1 which binds to the catalytic domain of the enzyme during ATP hydrolysis. The main role of IF1 consists of limiting ATP dissipation under condition of severe oxygen deprivation or in the presence of dysfunctions of mitochondrial respiratory complexes, causing a collapse in mitochondrial membrane potential and therefore ATP hydrolysis. New roles of IF1 are emerging in the fields of cancer and neurodegeneration. Its high expression levels in tumor tissues have been associated with different roles favouring tumor formation, progression and evasion. Since discordant mechanisms of action have been proposed for IF1 in tumors, it is of the utmost importance to clarify them in the prospective of defining novel approaches for cancer therapy. Other IF1 functions, including its involvement in mitophagy, may be protective for neurodegenerative and aging-related diseases. In the present review we aim to clarify and discuss the emerging mechanisms in which IF1 is involved, providing a critical view of the discordant findings in the literature
Polyamidoamide Dendrimers and Cross-Linking Agents for Stabilized Bioenzymatic Resistant Metal-Free Bovine Collagen
The work reports the use of polyamidoamine dendrimers (PAMAM) and a cross-linking agent, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) or 4-(4,6-dimethoxy[1,3,5]triazin-2-yl)-4-methyl-morpholinium chloride (DMTMM), for the thermal stabilization of dermal bovine collagen. The efficiency of EDC/NHS/PAMAM and DMTMM/PAMAM in the cross-linking of collagen is correlated to the increase of the collagen shrinkage temperature (Ts), measured by differential scanning calorimetry (DSC). An alternative enzymatic protocol was adopted to measure the degradability of EDC/NHS/PAMAM tanned hides; these data are correlated to the thermal stability values measured by DSC. In the presence of PAMAMs, EDC/NHS provides very high stabilization of bovine dermal collagen, giving Ts of up to 95 °C, while DMTMM achieves lower stabilization. Preliminary tanning tests carried out in best reaction conditions show that EDC/NHS/PAMAM could be an interesting, environmentally-sustainable tanning system which is completely free of metals, formaldehyde, and phenols. Two new unreported dendrimeric species were synthesized and employed
Corpo-identitĂ -soggetto. Un seminario
Nel 2016 con un gruppo di dottorandi di Spettacolo dell’Università la Sapienza di Roma, abbiamo tenuto un seminario che si proponeva di riflettere sulla relazione tra corpo, identità e soggetto nelle pratiche teatrali contemporanee. Le tre categorie sono state infatti ambito di riflessione tanto in campo filosofico quanto in quello teatrale. Il seminario nasce da un’interrogazione intorno al termine ʻcorpoʼ, sopravvenuta a partire dalle questioni che la tesi di Dalila D’amico, Le aporie del corpo eccentrico, sollevavano. Che cosa si intende per corpo, di che cosa si parla quando si parla di corpo? Perché si parla di corpo e non di soggetto? Quali funzioni esplica il corpo-identità -soggetto in scena nel repertorio di spettacoli, ambito delle nostre indagini? Quali autori, studiosi, testi ci sono stati d’aiuto per elaborare le nostre analisi e trovare le risposte ai nostri interrogativi
Plastics today: Key challenges and EU strategies towards carbon neutrality: A review
Never as today the need for collaborative interactions between industry, the scientific community, NGOs, policy makers and citizens has become crucial for the development of shared political choices and protection of the environment, for the safeguard of future generations. The complex socio-economic and environmental interconnections that underlie the EU strategy of the last years, within the framework of the Agenda 2030 and the green deal, often create perplexity and confusion that make difficult to outline the definition of a common path to achieve carbon neutrality and “net zero emissions” by 2050. Scope of this work is to give a general overview of EU policies, directives, regulations, and laws concerning polymers and plastic manufacturing, aiming to reduce plastic pollution, allowing for a better understanding of the implications that environmental concern and protection may generate from a social-economical point of view
Effect of TiO2 and Al2O3 Addition on the Performance of Chitosan/Phosphotungstic Composite Membranes for Direct Methanol Fuel Cells
: Composite chitosan/phosphotungstic acid (CS/PTA) with the addition of TiO2 and Al2O3 particles were synthesized to be used as proton exchange membranes in direct methanol fuel cells (DMFCs). The influence of fillers was assessed through X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, liquid uptake, ion exchange capacity and methanol permeability measurements. The addition of TiO2 particles into proton exchange membranes led to an increase in crystallinity and a decrease in liquid uptake and methanol permeability with respect to pristine CS/PTA membranes, whilst the effect of the introduction of Al2O3 particles on the characteristics of membranes is almost the opposite. Membranes were successfully tested as proton conductors in a single module DMFC of 1 cm2 as active area, operating at 50 °C fed with 2 M methanol aqueous solution at the anode and oxygen at the cathode. Highest performance was reached by using a membrane with TiO2 (5 wt.%) particles, i.e., a power density of 40 mW cm-2, almost doubling the performance reached by using pristine CS/PTA membrane (i.e., 24 mW cm-2)
Synthesis and Antimicrobial Evaluation of Bis-morpholine Triazine Quaternary Ammonium Salts
Efficient, environmentally and economically sustainable, and nontoxic antibacterial products are of global relevance in the fight against microorganism contamination. In this work, an easy and straightforward method for the synthesis of bis-morpholino triazine quaternary ammonium salts (bis-mTQAS) is reported, starting from 2,4,6-trichloro-1,3,5-triazine or 2,4-dichloro-6-methoxy-1,3,5-triazine and various N-alkylmorpholines. Bis-mTQAS were tested as antimicrobials against Gram-negative and Gram-positive bacterial strains. The best-performing bis-mTQAS were found to achieve total disinfection against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 at 50 and 400 μg/mL, respectively. Distinctively, bis-mTQAS with the highest antimicrobial efficiency had lowest cytotoxicity. © 2021 The Authors. ChemMedChem published by Wiley-VCH Gmb
Non-Natural Linker Configuration in 2,6-Dipeptidyl-Anthraquinones Enhances the Inhibition of TAR RNA Binding/Annealing Activities by HIV-1 NC and Tat Proteins
The HIV-1 nucleocapsid (NC) protein represents an excellent molecular target for the development of antiretrovirals
by virtue of its well-characterized chaperone activities, which play pivotal roles in essential steps of the viral life cycle.
Our ongoing search for candidates able to impair NC binding/annealing activities led to the identification of peptidylanthraquinones
as a promising class of nucleic acid ligands. Seeking to elucidate the inhibition determinants and increase the
potency of this class of compounds, we have now explored the effects of chirality in the linker connecting the planar nucleus to
the basic side chains. We show here that the non-natural linker configuration imparted unexpected TAR RNA targeting
properties to the 2,6-peptidyl-anthraquinones and significantly enhanced their potency. Even if the new compounds were able to
interact directly with the NC protein, they manifested a consistently higher affinity for the TAR RNA substrate and their TARbinding
properties mirrored their ability to interfere with NC-TAR interactions. Based on these findings, we propose that the
viral Tat protein, sharing the same RNA substrate but acting in distinct phases of the viral life cycle, constitutes an additional
druggable target for this class of peptidyl-anthraquinones. The inhibition of Tat-TAR interaction for the test compounds
correlated again with their TAR-binding properties, while simultaneously failing to demonstrate any direct Tat-binding
capabilities. These considerations highlighted the importance of TAR RNA in the elucidation of their inhibition mechanism,
rather than direct protein inhibition. We have therefore identified anti-TAR compounds with dual in vitro inhibitory activity on
different viral proteins, demonstrating that it is possible to develop multitarget compounds capable of interfering with processes
mediated by the interactions of this essential RNA domain of HIV-1 genome with NC and Tat proteins
- …