85 research outputs found

    Possible A2E Mutagenic Effects on RPE Mitochondrial DNA from Innovative RNA-Seq Bioinformatics Pipeline

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    Mitochondria are subject to continuous oxidative stress stimuli that, over time, can impair their genome and lead to several pathologies, like retinal degenerations. Our main purpose was the identification of mtDNA variants that might be induced by intense oxidative stress determined by N-retinylidene-N-retinylethanolamine (A2E), together with molecular pathways involving the genes carrying them, possibly linked to retinal degeneration. We performed a variant analysis comparison between transcriptome profiles of human retinal pigment epithelial (RPE) cells exposed to A2E and untreated ones, hypothesizing that it might act as a mutagenic compound towards mtDNA. To optimize analysis, we proposed an integrated approach that foresaw the complementary use of the most recent algorithms applied to mtDNA data, characterized by a mixed output coming from several tools and databases. An increased number of variants emerged following treatment. Variants mainly occurred within mtDNA coding sequences, corresponding with either the polypeptide-encoding genes or the RNA. Time-dependent impairments foresaw the involvement of all oxidative phosphorylation complexes, suggesting a serious damage to adenosine triphosphate (ATP) biosynthesis, that can result in cell death. The obtained results could be incorporated into clinical diagnostic settings, as they are hypothesized to modulate the phenotypic expression of mtDNA pathogenic variants, drastically improving the field of precision molecular medicine

    Generation of cytocompatible superhydrophobic Zr–Cu–Ag metallic glass coatings with antifouling properties for medical textiles

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    Zirconium–Copper-based metallic glass thin films represent promising coatings in the biomedical sector for their combination of antibacterial property and wear resistance. However, finding a Zr–Cu metallic glass composition with desirable cytocompatibility and antibacterial property is extremely challenging. In this work, we have created a cytocompatible and (super-)hydrophobic Zr–Cu–Ag metallic glass coating with ≈95% antifouling properties. First, a range of different chemical compositions were prepared via Physical Vapor Deposition magnetron by co-sputtering Zr, Cu, and Ag onto a Polybutylene terephthalate (PBT) substrate among which Zr93·5Cu6·2Ag0.2, Zr76·7Cu22·7Ag0.5, and Zr69·3Cu30·1Ag0.6 were selected to be further investigate for their surface properties, antibacterial activity, and cytocompatibility. Scanning electron microscopy (SEM) images revealed a micro-roughness fibrous structure holding superhydrophobic properties demonstrated by specimens' static and dynamic contact angle measurements ranging from 130° to 150°. The dynamic contact angle measurements have shown hysteresis below 10° for all coated samples which indicated the superhydrophobicity of the samples. To distinguish between antifouling and bactericidal effect of the coating, ions release from coatings into Luria Bertani Broth (LB), and Dulbecco's Modified Eagle Medium (DMEM) solutions were evaluated by inductively coupled plasma mass spectrometry (ICP-MS) measurements after 24 ​h and 5 days. Antifouling properties were evaluated by infecting the specimens' surface with the Gram-positive Staphylococcus aureus and the Gram-negative Escherichia coli strain reporting a ≈95% reduction of bacteria adhesion as visually confirmed by FESEM and fluorescent live/dead staining. Human mesenchymal stem cells (hMSC) were used for direct cytocompatibility evaluation of coated samples and their metabolic activity was evaluated via relative fluorescence unit after 24 ​h and 5 days confirming that it was comparable to the controls (>97% viable cells). The results were further visualized by FESEM, fluorescent staining by Live/Dead Viability/Cytotoxicity Kit and confirmed the cytocompatibility of all coated samples. Finally, hMSC′ cytoplasm was stained by May Grunwald and Giemsa after 5days to detect and visualize the released ions which have diffused through the cells' membrane

    Grafting of alpha-tocopheryl phosphate on chemically treated Ti-6Al-4V for antibacterial bone implants

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    Alpha-tocopheryl phosphate ( tocopherol. Even if α α-TP) is the water-soluble form of the antioxidant and lipophilic molecule alpha- -TP’s antioxidant and antibacterial properties are known, it has never been exploited to prevent implantable materials against bacterial surface contamination, till now. Accordingly, the purpose of this work is to couple a chemically treated Ti6Al4V surface with α-TP conferring a local antibacterial activity preserving orthopaedic and dental prosthetic devices. The grafting of the α-TP molecule is explored both as a thin coating (3 logs (≈ 92%) in comparison to the uncoated controls. Contrarily, the phosphorylated groups were used to create the binding to the surface on the functionalized samples, as shown by the XPS analysis. The functionalized surface results in poor antibacterial properties (≈1 log reduction of viable colonies) and hydrophobic behaviour. Finally, the cytocompatibility evaluation towards human mesenchymal stem cells showed the coating treatment to be more cell’s friendly in comparison with the functionalization

    Placental Chorangiocarcinoma a Specific Histological Pattern of Uncertain Incidence and Clinical Impact: Systematic Review of the Literature

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    Chorangiocarcinoma is a very rare and misdiagnosed placental neoplasm. The unique morphologic features of the lesion distinguish it from other trophoblastic tumors and vascular abnormalities. We present a systematic review of the literature to provide clarity on chorangiocarcinoma entity and biology. A literature search was carried out in December 2022 using the keywords "Placental chorangiocarcinoma", "Chorangioma", "Placenta", and "Throphoblast proliferation". Articles published from 1988 to 2022 were obtained from Scopus, Google Scholar, and PUBMED. In our review, we examined maternal age, gestational age at the time of delivery, parity, type of pregnancy, placental weight, ultrasound features of the placenta, macroscopic examination and tumor size, microscopic examination, immunostaining, maternal beta-human chorionic gonadotropin, fetal and maternal outcome. Eight manuscripts were detected. They are all case reports. The macroscopic characteristics of the lesions were represented by the presence of a grey-yellow-white color well-demarcated round nodule. Microscopically, all the authors described typical aspects of malignancy as a high rate of mitosis, nuclear atypia and necrotic areas. In some cases, the presence of AE1/AE3 cytoplasmic positivity, p63 nuclear staining, and beta-human chorionic gonadotropin (BHCG) were reported. A good fetal outcome was reported in all cases of newborns with normal birth weight, except one with fetal growth restriction. Maternal outcome was good in all cases except one with maternal lung metastasis three months after delivery. The clinical course has probably underestimated the real incidence of the pathology. Only greater knowledge of its histology and its clinical course will allow us to evaluate the real prevalence of the disease

    Topographical and Biomechanical Guidance of Electrospun Fibers for Biomedical Applications

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    Electrospinning is gaining increasing interest in the biomedical field as an eco-friendly and economic technique for production of random and oriented polymeric fibers. The aim of this review was to give an overview of electrospinning potentialities in the production of fibers for biomedical applications with a focus on the possibility to combine biomechanical and topographical stimuli. In fact, selection of the polymer and the eventual surface modification of the fibers allow selection of the proper chemical/biological signal to be administered to the cells. Moreover, a proper design of fiber orientation, dimension, and topography can give the opportunity to drive cell growth also from a spatial standpoint. At this purpose, the review contains a first introduction on potentialities of electrospinning for the obtainment of random and oriented fibers both with synthetic and natural polymers. The biological phenomena which can be guided and promoted by fibers composition and topography are in depth investigated and discussed in the second section of the paper. Finally, the recent strategies developed in the scientific community for the realization of electrospun fibers and for their surface modification for biomedical application are presented and discussed in the last section

    Deposition of Antioxidant and Cytocompatible Caffeic Acid-Based Thin Films onto Ti6Al4V Alloys through Hexamethylenediamine-Mediated Crosslinking

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    A promising approach for advanced bone implants is thedepositionon titanium surfaces of organic thin films with improved therapeuticperformances. Herein, we reported the efficient dip-coating depositionof caffeic acid (CA)-based films on both polished and chemically pre-treatedTi6Al4V alloys by exploiting hexamethylenediamine (HMDA) crosslinkingability. The formation of benzacridine systems, resulting from theinteraction of CA with the amino groups of HMDA, as reported in previousstudies, was suggested by the yellow/green color of the coatings.The coated surfaces were characterized by means of the Folin-Ciocalteumethod, fluorescence microscopy, water contact angle measurements,X-ray photoelectron spectroscopy (XPS), zeta-potential measurements,and Fourier transform infrared spectroscopy, confirming the presenceof a uniform coating on the titanium surfaces. The optimal mechanicaladhesion of the coating, especially on the chemically pre-treatedsubstrate, was also demonstrated by the tape adhesion test. Interestingly,both films exhibited marked antioxidant properties (2,2-diphenyl-1-picrylhydrazyland ferric reducing antioxidant power assays) that persisted overtime and were not lost even after prolonged storage of the material.The feature of the coatings in terms of the exposed groups (XPS andzeta potential titration evidence) was apparently dependent on thesurface pre-treatment of the titanium substrate. Cytocompatibility,scavenger antioxidant activity, and antibacterial properties of thedeveloped coatings were evaluated. The most promising results wereobtained in the case of the chemically pre-treated CA/HMDA-based coatedsurface that showed good cytocompatibility and high reactive oxygenspecies' scavenging ability, preventing their intracellularaccumulation under pro-inflammatory conditions; moreover, an anti-foulingeffect preventing the formation of 3D biofilm-like bacterial aggregateswas observed by scanning electron microscopy. These results open newperspectives for the development of innovative titanium surfaces withthin coatings from naturally occurring phenols for bone contact implants
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