123 research outputs found

    Novel Technique of Transepithelial Corneal Cross-Linking Using Iontophoresis in Progressive Keratoconus

    Get PDF
    In this work, the authors presented the techniques and the preliminary results at 6 months of a randomized controlled trial (NCT02117999) comparing a novel transepithelial corneal cross-linking protocol using iontophoresis with the Dresden protocol for the treatment of progressive keratoconus. At 6months, there was a significant average improvement with an average flattening of themaximum simulated keratometry reading of 0.72\ub11.20D(P = 0.01); in addition, corrected distance visual acuity improved significantly (P = 0.08) and spherical equivalent refraction was significantly lessmyopic (P = 0.02) 6months a\u17fter transepithelial corneal cross-linkingwith iontophoresis. The novel protocol using iontophoresis showed comparable resultswith standard corneal cross-linking to halt progression of keratoconus during 6-month follow-up. Investigation of the long-term RCT outcomes are ongoing to verify the efficacy of this transepithelial corneal cross-linking protocol and to determine if it may be comparable with standard corneal cross-linking in themanagement of progressive keratoconus

    Visualization of DNA G-quadruplexes in herpes simplex virus 1-infected cells

    Get PDF
    We have previously shown that clusters of guanine quadruplex (G4) structures can form in the human herpes simplex-1 (HSV-1) genome. Here we used immunofluorescence and immune-electron microscopy with a G4-specific monoclonal antibody to visualize G4 structures in HSV-1 infected cells. We found that G4 formation and localization within the cells was virus cycle dependent: viral G4s peaked at the time of viral DNA replication in the cell nucleus, moved to the nuclear membrane at the time of virus nuclear egress and were later found in HSV-1 immature virions released from the cell nucleus. Colocalization of G4s with ICP8, a viral DNA processing protein, was observed in viral replication compartments. G4s were lost upon treatment with DNAse and inhibitors of HSV-1 DNA replication. The notable increase in G4s upon HSV-1 infection suggests a key role of these structures in the HSV-1 biology and indicates new targets to control both the lytic and latent infection

    A microfabricated physical sensor for atmospheric mercury monitoring

    Get PDF
    Abstract A new microfabricated physical sensor for elemental gaseous mercury (Hg 0 ) determinations has been developed and experimentally tested by the authors. Hg 0 represents 90-99% of atmospheric mercury forms. The sensor is based on the technique of resistivity variation of thin gold film, characterised by high selectivity and absence of optical parts. The sensor consists of four identical thin gold film resistors mounted in Wheatstone bridge configuration. Two resistors work as sensitive elements and the others as reference, in order to minimise the influence of temperature variation. The absorption of Hg 0 on the gold film produces a change in the resistivity of the amalgam. Far from the saturation, this change is proportional to the amount of the absorbed Hg 0 . The adsorption behaviour of the sensor deposited by sputtering on two different substrates (glass and Printed Circuit Board (PCB)) have been investigated. The sensors showed to work in a large range of linearity and need a low power during the regeneration process. Sensors on glass and PCB substrates underwent numerous regeneration cycles without inflicting any mechanical or electrical damages to the resistors. The presented experimental results describe the features of both sensors pointing out advantages and drawbacks of the used substrates. The PCB substrate seems to have more suitable characteristics for developing a new mercury 'smart' sensor

    RISK FACTORS FOR VOLUNTARY INTERRUPTION OF PREGNANCY AND POSSIBLE PREVENTIVE PUBLIC HEALTH ACTIONS

    Get PDF
    Introduction. Voluntary interruption of pregnancy (VIP) is one of the most frequent healthcare procedures in the world and a Public Health concern in many countries, especially after liberalization of the abortion laws. The study has been carried out to identify the factors that still influence a fraction of female population towards abortion in the absence of fetal malformations.Methods. We conducted a cross-sectional study in the period 2012-2016. The survey was carried out on all VIPs performed at the Gynecology and Obstetrics Unit of the University Hospital "G. Martino" in Messina, Italy. Results. The analyzed sample consisted of 1131 women, aged between 16 and 50 years. Only 4% of VIPs was due to a diagnosis of fetal malformation. In relation to the presence or absence of fetal malformations as the possible reason for VIP, the sample was split up into two groups and the socio-demographic characteristics were considered. VIPs in the absence of malformations were significantly more frequent in younger women with a lower educational level, in unmarried and unemployed women and in women who already had children. Multivariate analysis, including as covariates education level, marital status, profession, number of children, number of previous abortions and nationality, indicated that the variables mainly related to using VIP in the absence of malformations were marital status, age and number of sons.Conclusions. Based on our results, it is crucial to further prevent requests for VIPs through information and sex education programs for adolescents in schools and consultants, and responsible procreation promotion programs

    Electrically-Responsive Reversible Polyketone/MWCNT Network through Diels-Alder Chemistry

    Get PDF
    This study examines the preparation of electrically conductive polymer networks based on furan-functionalised polyketone (PK-Fu) doped with multi-walled carbon nanotubes (MWCNTs) and reversibly crosslinked with bis-maleimide (B-Ma) via Diels-Alder (DA) cycloaddition. Notably, the incorporation of 5 wt.% of MWCNTs results in an increased modulus of the material, and makes it thermally and electrically conductive. Analysis by X-ray photoelectron spectroscopy indicates that MWCNTs, due to their diene/dienophile character, covalently interact with the matrix via DA reaction, leading to effective interfacial adhesion between the components. Raman spectroscopy points to a more effective graphitic ordering of MWCNTs after reaction with PK-Fu and B-Ma. After crosslinking the obtained composite via the DA reaction, the softening point (tan(delta) in dynamic mechanical analysis measurements) increases up to 155 degrees C, as compared to the value of 130 degrees C for the PK-Fu crosslinked with B-Ma and that of 140 degrees C for the PK-Fu/B-Ma/MWCNT nanocomposite before resistive heating (responsible for crosslinking). After grinding the composite, compression moulding (150 degrees C/40 bar) activates the retro-DA process that disrupts the network, allowing it to be reshaped as a thermoplastic. A subsequent process of annealing via resistive heating demonstrates the possibility of reconnecting the decoupled DA linkages, thus providing the PK networks with the same thermal, mechanical, and electrical properties as the crosslinked pristine systems

    Inhibition of Stearoyl-CoA desaturase 1 reverts BRAF and MEK inhibition-induced selection of cancer stem cells in BRAF-mutated melanoma

    Get PDF
    Combination therapy with BRAF and MEK inhibitors significantly improves survival in BRAF mutated melanoma patients but is unable to prevent disease recurrence due to the emergence of drug resistance. Cancer stem cells (CSCs) have been involved in these long-term treatment failures. We previously reported in lung cancer that CSCs maintenance is due to altered lipid metabolism and dependent upon Stearoyl-CoA-desaturase (SCD1)-mediated upregulation of YAP and TAZ. On this ground, we investigated the role of SCD1 in melanoma CSCs

    Correction of Mutant p63 in EEC Syndrome Using siRNA Mediated Allele-Specific Silencing Restores Defective Stem Cell Function

    Get PDF
    Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) syndrome is a rare autosomal dominant disease caused by heterozygous mutations in the p63 gene and characterized by limb defects, orofacial clefting, ectodermal dysplasia, and ocular defects. Patients develop progressive total bilateral limbal stem cell deficiency, which eventually results in corneal blindness. Medical and surgical treatments are ineffective and of limited benefit. Oral mucosa epithelial stem cells (OMESCs) represent an alternative source of stem cells capable of regenerating the corneal epithelium and, combined with gene therapy, could provide an attractive therapeutic avenue. OMESCs from EEC patients carrying the most severe p63 mutations (p.R279H and p.R304Q) were characterized and the genetic defect of p.R279H silenced using allele-specific (AS) small interfering RNAs (siRNAs). Systematic screening of locked nucleic acid (LNA)-siRNAs against R279H-p63 allele in (i) stable WT-\u394Np63\u3b1-RFP and R279H-\u394Np63\u3b1-EGFP cell lines, (ii) transient doubly transfected cell lines, and (iii) p.R279H OMESCs, identified a number of potent siRNA inhibitors for the mutant allele, which had no effect on wild-type p63. In addition, siRNA treatment led to longer acquired life span of mutated stem cells compared to controls, less accelerated stem cell differentiation in vitro, reduced proliferation properties, and effective ability in correcting the epithelial hypoplasia, thus giving rise to full thickness stratified and differentiated epithelia. This study demonstrates the phenotypic correction of mutant stem cells (OMESCs) in EEC syndrome by means of siRNA mediated AS silencing with restoration of function. The application of siRNA, alone or in combination with cell-based therapies, offers a therapeutic strategy for corneal blindness in EEC syndrome

    Hydrogel-in-hydrogel live bioprinting for guidance and control of organoids and organotypic cultures

    Get PDF
    Three-dimensional hydrogel-based organ-like cultures can be applied to study development, regeneration, and disease in vitro. However, the control of engineered hydrogel composition, mechanical properties and geometrical constraints tends to be restricted to the initial time of fabrication. Modulation of hydrogel characteristics over time and according to culture evolution is often not possible. Here, we overcome these limitations by developing a hydrogel-in-hydrogel live bioprinting approach that enables the dynamic fabrication of instructive hydrogel elements within pre-existing hydrogel-based organ-like cultures. This can be achieved by crosslinking photosensitive hydrogels via two-photon absorption at any time during culture. We show that instructive hydrogels guide neural axon directionality in growing organotypic spinal cords, and that hydrogel geometry and mechanical properties control differential cell migration in developing cancer organoids. Finally, we show that hydrogel constraints promote cell polarity in liver organoids, guide small intestinal organoid morphogenesis and control lung tip bifurcation according to the hydrogel composition and shape
    • 

    corecore