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1.
Graefes Arch Clin Exp Ophthalmol ; 259(12): 3721-3727, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34436645

RESUMEN

PURPOSE: The purpose of this study is to investigate whether phacoemulsification can generate aerosolized single-stranded RNA (ssRNA) and retain sequence integrity using an artificial eye model for experimental cataract surgery. METHODS: A simulation of cataract surgery was performed using an anterior chamber eye model filled with an ssRNA probe at different scalar dilutions (kanamycin positive control ssRNA). A plastic conical cage was built over the artificial eye surface of the mock-up. A total of 24 tests (twice reproduced) were performed, and five nitrocellulose strips were placed 15 cm from the artificial surface of the mock-up and used to collect aerosol particles, from each experiment. Phaco-activity was mimicked using a phacoemulsification equipped with a 2.75-mm tip, and strips were removed at the end of the procedure. RNA extraction, reverse transcription, and agarose gel electrophoresis were performed and compared. RESULTS: Strips collected aerosol droplets enriched with ssRNA, mainly at the higher concentrations tested, compared to related untouched standard solutions. Complementary DNA (cDNA) synthesis confirmed the presence of intact ssRNA fragments. As observed from densitometric analysis of resolved RNA in extracted samples and cDNA bands after retro-transcription, lower concentrations of ssRNA were also detected. CONCLUSIONS: As the main output of the study, the phaco-generated aerosol can deliver an intact ssRNA sequence. Since the aerosol can potentially reach the operator's face, any biological agent (virus/bacteria) potentially inside the anterior chamber of a patient undergoing cataract surgery, eventually escaping from biomolecular checks, can be potentially infective for operators. The data reported herein suggest that collective versus individual protective countermeasures should always be encouraged in ocular surgery and should not be restricted to coronavirus disease emergencies.


Asunto(s)
Extracción de Catarata , Catarata , Ácidos Nucleicos , Facoemulsificación , Aerosoles , Humanos
2.
Adv Exp Med Biol ; 1331: 265-273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34453305

RESUMEN

Nerve growth factor (NGF) plays a crucial role in retinal disorders, as suggested by in vitro/in vivo models. The major effect embraces the neuroprotective activity on retinal ganglion cells (RGCs) undergoing degeneration, as observed in experimental diabetic retinopathy, age-related and diabetic macular degeneration, and some vitreoretinal diseases. Focused experiments suggested that locally applied NGF (intravitreal delivery) not only allowed the counteraction of RGC degeneration but also provided data for a whole retina restoration. The currently available retinal microsurgery allows the collection of human aqueous and more interesting vitreous (vitreal reflux) humors. The recent biomolecular analysis highlights the possibility to identify disease-associated biomarkers and allow the monitoring of retinal impairments with sustain to the retinal imaging. Coupled to other soluble mediators, NGF has been quantified in aqueous (slightly expressed) from diabetic retinopathy-suffering patients (cataract surgery) and vitreal reflux (significantly impaired) of diabetic macular degeneration-suffering patients (intravitreal surgery). Although the reasons of these NGF impairments are not fully comprehended, some retinal cells (glial cells, bipolar neurons, and RGCs) have been recognized partially responsible for these local changes.Taken together, the recent progress in the ocular microsurgeries might be associated with sampling of small amount of ocular humors, allowing the collection of biochemical information about diseased retina and the monitoring of treatment. The chance to detect NGF and likewise other neuroprotective or pro-/anti-inflammatory factors in these fluids would open to the possibility to identify biomarkers of early diagnosis or monitoring of retinal disease evolution/therapy (precision medicine).


Asunto(s)
Factor de Crecimiento Nervioso , Enfermedades Neurodegenerativas , Humanos , Neuroprotección , Retina , Células Ganglionares de la Retina
3.
J Virol ; 90(10): 4926-38, 2016 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-26937030

RESUMEN

UNLABELLED: Human cytomegalovirus (HCMV) is a major cause of morbidity and mortality in transplant patients and is the leading viral cause of birth defects after congenital infection. HCMV infection relies on the recognition of cell-specific receptors by one of the viral envelope glycoprotein complexes. Either the gH/gL/gO or the gH/gL/UL128/UL130/UL131A (Pentamer) complex has been found to fulfill this role, accounting for HCMV entry into almost all cell types. We have studied the UL116 gene product, a putative open reading frame identified by in silico analysis and predicted to code for a secreted protein. Virus infection experiments in mammalian cells demonstrated that UL116 is expressed late in the HCMV replication cycle and is a heavily glycosylated protein that first localizes to the cellular site of virus assembly and then inserts into the virion envelope. Transient-transfection studies revealed that UL116 is efficiently transported to the plasma membrane when coexpressed with gH and that gL competes with UL116 for gH binding. Further evidence for gH/UL116 complex formation was obtained by coimmunoprecipitation experiments on both transfected and infected cells and biochemical characterization of the purified complex. In summary, our results show that the product of the UL116 gene is an HCMV envelope glycoprotein that forms a novel gH-based complex alternative to gH/gL. Remarkably, the gH/UL116 complex is the first herpesvirus gH-based gL-less complex. IMPORTANCE: HCMV infection can cause severe disease in immunocompromised adults and infants infected in utero The dissection of the HCMV entry machinery is important to understand the mechanism of viral infection and to identify new vaccine antigens. The gH/gL/gO and gH/gL/UL128/UL130/UL131 (Pentamer) complexes play a key role in HCMV cell entry and tropism. Both complexes are formed by an invariant gH/gL scaffold on which the other subunits assemble. Here, we show that the UL116 gene product is expressed in infected cells and forms a heterodimer with gH. The gH/UL116 complex is carried on the infectious virions, although in smaller amounts than gH/gL complexes. No gH/UL116/gL ternary complex formed in transfected cells, suggesting that the gH/UL116 complex is independent from gL. This new gH-based gL-free complex represents a potential target for a protective HCMV vaccine and opens new perspectives on the comprehension of the HCMV cell entry mechanism and tropism.


Asunto(s)
Citomegalovirus/genética , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/metabolismo , Animales , Línea Celular , Citomegalovirus/química , Genoma Viral , Humanos , Microscopía Electrónica , Mutación , Multimerización de Proteína , Transfección , Proteínas del Envoltorio Viral/química , Ensamble de Virus , Internalización del Virus
4.
Immunol Cell Biol ; 94(9): 849-860, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27192938

RESUMEN

Human cytomegalovirus (HCMV) is known to exert suppressive effects on the host immune system through expression of various viral genes, thus directly and indirectly affecting antiviral immunity of the infected individuals. We report here that HCMV UL10 encodes a protein (pUL10) with immunosuppressive properties. UL10 has been classified as a member of the HCMV RL11 gene family. Although pUL10 is known to be dispensable for viral replication in cultured cells, its amino-acid sequence is well conserved among different HCMV isolates, suggesting that the protein has a crucial role in viral survival in the host environment. We show that pUL10 is cleaved from the cell surface of fibroblasts as well as epithelial cells and interacts with a cellular receptor ubiquitously expressed on the surface of human leukocytes, demonstrated by ex vivo cell-based assays and flow cytometric analyses on both lymphoid cell lines and primary blood cells. Furthermore, preincubation of peripheral blood mononuclear cells with purified pUL10 ectodomain results in significantly impaired proliferation and substantially reduced pro-inflammatory cytokine production, in particular in CD4+ T cells upon in vitro T-cell stimulation. The inhibitory effect of pUL10 is also observed on antigen receptor-mediated intracellular tyrosine phosphorylation in a T-cell line. Based on these observations, we suggest that pUL10 is a newly identified immunomodulatory protein encoded by HCMV. Further elucidation of interactions between pUL10 and the host immune system during HCMV may contribute to finding ways towards new therapies for HCMV infection.


Asunto(s)
Proteínas de la Cápside/metabolismo , Activación de Linfocitos/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Secuencia de Aminoácidos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Proteínas de la Cápside/química , Línea Celular , Membrana Celular/metabolismo , Proliferación Celular , Citocinas/biosíntesis , Glicosilación , Células HEK293 , Humanos , Proteínas de la Membrana/metabolismo , Proteínas Recombinantes/metabolismo , Transducción de Señal
5.
ACS Appl Mater Interfaces ; 16(1): 1293-1307, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38134036

RESUMEN

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal-TiO2 micromotors with different metal materials to investigate the impact of electronic properties of the metal-semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion. By asymmetrically depositing Au or Ag layers on thermally annealed Ti3C2Tx MXene microparticles using sputtering, Janus structures are formed with Schottky junctions at the metal-semiconductor interface. Under UV light irradiation, Au-TiO2 micromotors show higher self-propulsion velocities due to the stronger built-in electric field, enabling efficient photogenerated charge carrier separation within the semiconductor and higher hole accumulation beneath the Au layer. On the contrary, in 0.1 wt % H2O2, Ag-TiO2 micromotors reach higher velocities both in the presence and absence of UV light irradiation, owing to the superior catalytic properties of Ag in H2O2 decomposition. Due to the widespread use of plastics and polymers, and the consequent occurrence of nano/microplastics and polymeric waste in water, Au-TiO2 micromotors were applied in water remediation to break down polyethylene glycol (PEG) chains, which were used as a model for polymeric pollutants in water. These findings reveal the interplay between electronic properties and catalytic activity in metal-semiconductor junctions, offering insights into the future design of powerful light-driven micro- and nanomotors with promising implications for water treatment and photocatalysis applications.

6.
Nanomaterials (Basel) ; 13(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36985965

RESUMEN

The electrochemical hydrogen evolution reaction (HER) is one of the most promising green methods for the efficient production of renewable and sustainable H2, for which platinum possesses the highest catalytic activity. Cost-effective alternatives can be obtained by reducing the Pt amount and still preserving its activity. The Pt nanoparticle decoration of suitable current collectors can be effectively realized by using transition metal oxide (TMO) nanostructures. Among them, WO3 nanorods are the most eligible option, thanks to their high stability in acidic environments, and large availability. Herein, a simple and affordable hydrothermal route is used for the synthesis of hexagonal WO3 nanorods (average length and diameter of 400 and 50 nm, respectively), whose crystal structure is modified after annealing at 400 °C for 60 min, to obtain a mixed hexagonal/monoclinic crystal structure. These nanostructures were investigated as support for the ultra-low-Pt nanoparticles (0.2-1.13 µg/cm2): decoration occurs by drop casting some drops of a Pt nanoparticle aqueous solution and the electrodes were tested for the HER in acidic environment. Pt-decorated WO3 nanorods were characterized by performing scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), Rutherford backscattering spectrometry (RBS), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and chronopotentiometry. HER catalytic activity is studied as a function of the total Pt nanoparticle loading, thus obtaining an outstanding overpotential of 32 mV at 10 mA/cm2, a Tafel slope of 31 mV/dec, a turn-over frequency of 5 Hz at -15 mV, and a mass activity of 9 A/mg at 10 mA/cm2 for the sample decorated with the highest Pt amount (1.13 µg/cm2). These data show that WO3 nanorods act as excellent supports for the development of an ultra-low-Pt-amount-based cathode for efficient and low-cost electrochemical HER.

7.
Sci Rep ; 13(1): 3203, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36828859

RESUMEN

Bimetallic decoration of semiconductor electrodes typically improves catalytic and sensing performances because of a well-claimed synergistic effect. A microscopic and quantitative investigation of such an effect on energy bands of semiconductor can be really useful for further exploitation. Au, Pd and Au@Pd (core@shell) nanoparticles (10-20 nm in size) were synthesized through chemical reduction method and characterized with scanning and transmission microscopy, Rutherford backscattering spectrometry, cyclic voltammetry electrochemical impedance spectroscopy and Mott-Schottky analysis. The nanoparticles have been used to decorate Ni-based nanostructured electrodes with the aim to quantitatively investigate the effect of decoration with mono or bimetallic nanoparticles. Decorated electrodes show higher redox currents than bare ones and a shift in redox peaks (up to 0.3 V), which can be ascribed to a more efficient electron transport and improved catalytic properties. These effects were satisfactorily modeled (COMSOL) employing a nano Schottky junction at the nanoparticle-semiconductor interface, pointing out large energy band bending (up to 0.4 eV), space charge region and local electric field (up to [Formula: see text]) in bimetallic decoration. Sensing test of glucose and H2O2 by decorated Ni oxide electrodes were performed to consolidate our model. The presence of bimetallic nanoparticles enhances enormously the electrochemical performances of the material in terms of sensitivity, catalytic activity, and electrical transport. The modification of energy band diagram in semiconductor is analyzed and discussed also in terms of electron transfer during redox reactions.

8.
Appl Radiat Isot ; 201: 110991, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37643555

RESUMEN

Melting of metallic waste reduces the waste volume, allows more accurate radiological characterization, and minimizes handling at the waste production site. This paper proposes a new non-destructive assay methodology to radiologically characterize low- and intermediate-level (LILW) waste before melting. A non-destructive assay technique is developed and qualified using geometry optimization technique and sample analysis after melting. Additionally, we present an operational methodology to predict the activity values of the major gamma emitters based on the average dose rate measurements.

9.
Appl Psychol Health Well Being ; 15(2): 776-802, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36261917

RESUMEN

The study demands-resources framework states that study demands increase exhaustion and study resources increase engagement. Study crafting describes a student's proactive adaption to demands and resources. To date, no intervention in the higher education context has aimed to foster study crafting. Accordingly, this study developed and evaluated the STUDYCoach online intervention, which aimed to increase engagement and reduce exhaustion by promoting study crafting. The study was a randomized controlled trial with a waiting-list control group. All participants (N = 209) completed a questionnaire before (T1) and after (T2) the intervention and at a 20-week follow-up (T3). Participants in the intervention group (n = 149) used the STUDYCoach over three consecutive weeks. Results showed that overall study crafting, decreasing hindering demands, and engagement significantly increased in the intervention group compared to the control group after the intervention. All effects remained stable at follow-up. Notably, exhaustion decreased significantly in the intervention group from T1 to T3 and T2 to T3. Study crafting mediated the intervention's effect on engagement and exhaustion. Our study extends the study demands-resources framework and the literature on job crafting by confirming that study crafting interventions can be effective in higher education.


Asunto(s)
Fatiga , Intervención basada en la Internet , Estudiantes , Fatiga/prevención & control , Fatiga/psicología , Humanos , Masculino , Femenino , Estudiantes/psicología , Promoción de la Salud , Servicios de Salud Escolar , Alemania , Adulto Joven , Universidades , Encuestas y Cuestionarios , Análisis Factorial , Abandono Escolar , Motivación
10.
ACS Omega ; 8(40): 37023-37031, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37841157

RESUMEN

The investigation of high-efficiency and sustainable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media is critical for renewable energy technologies. Here, we report a low-cost and high-yield method to obtain ZnOHF-ZnO-based 2D nanostars (NSs) by means of chemical bath deposition (CBD). The obtained NSs, cast onto graphene paper substrates, were used as active materials for the development of a full water splitting cell. For the HER, NSs were decorated with an ultralow amount of Pt nanoparticles (11.2 µg cm-2), demonstrating an overpotential of 181 mV at a current density of 10 mA cm-2. The intrinsic activity of Pt was optimized, thanks to the ZnO supporting nanostructures, as outlined by the mass activity of Pt (0.9 mA mgPt-1) and its turnover frequency (0.27 s-1 for a Pt loading of 11.2 µg cm-2). For the OER, bare NSs showed a remarkable result of 355 mV at 10 mA cm-2 in alkaline media. Pt-decorated and bare NSs were used as the cathode and anode, respectively, for alkaline electrochemical water splitting, assessing a stable overpotential of 1.7 V at a current density of 10 mA cm-2. The reported data pave the way toward large-scale production of low-cost electrocatalysts for green hydrogen production.

11.
Biomed Res Int ; 2022: 7497816, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36567907

RESUMEN

Background: A plethora of inflammatory, angiogenic, and tissue remodeling factors has been reported in idiopathic epiretinal membranes (ERMs). Herein we focused on the expression of a few mediators (oxidative, inflammatory, and angiogenic/vascular factors) by means of short-term vitreal cell cultures and biomolecular analysis. Methods: Thirty-nine (39) ERMs and vitreal samples were collected at the time of vitreoretinal surgery and biomolecular analyses were performed in clear vitreous, vitreal cell pellets, and ERMs. ROS products and iNOS were investigated in adherent vitreal cells and/or ERMs, and iNOS, VEGF, Ang-2, IFNγ, IL18, and IL22 were quantified in vitreous (ELISA/Ella, IF/WB); transcripts specific for iNOS, p65NFkB, KEAP1, NRF2, and NOX1/NOX4 were detected in ERMs (PCR). Biomolecular changes were analyzed and correlated with disease severity. Results: The higher ROS production was observed in vitreal cells at stage 4, and iNOS was found in ERMs and increased in the vitreous as early as at stage 3. Both iNOS and NOX4 were upregulated at all stages, while p65NFkB was increased at stage 3. iNOS and NOX1 were positively and inversely related with p65NFkB. While NOX4 transcripts were always upregulated, NRF2 was upregulated at stage 3 and inverted at stage 4. No significant changes occurred in the release of angiogenic (VEGF, Ang-2) and proinflammatory (IL18, IL22 and IFNγ) mediators between all stages investigated. Conclusions: ROS production was strictly associated with iNOS and NOX4 overexpression and increased depending on ERM stadiation. The higher iNOS expression occurred as early as stage 3, with respect to p65NFkB and NRF2. These last mediators might have potential prognostic values in ERMs as representative of an underneath retinal damage.


Asunto(s)
Membrana Epirretinal , Estrés Oxidativo , Especies Reactivas de Oxígeno , Humanos , Membrana Epirretinal/genética , Membrana Epirretinal/metabolismo , Interleucina-18/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Estrés Oxidativo/genética , Estrés Oxidativo/fisiología
12.
Mult Scler Relat Disord ; 63: 103814, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35487032

RESUMEN

BACKGROUND: Monoclonal antibodies have been a milestone in the treatment of multiple sclerosis (MS). Infective complications have been observed in patients on agents targeting lymphoid cells' surface antigens, namely anti-CD52 (alemtuzumab) and anti-CD20 agents (ocrelizumab and rituximab). Despite increasing emerging data, there is no standardized consensus regarding pre-treatment testing, vaccinations, and patient education before and during MS therapy or optimal infection-control strategies. METHODS: We led a retrospective/prospective real-life study to evaluate the effectiveness of a program of screening and prophylaxis for infective adverse events in patients with multiple sclerosis and related disorders treated with drugs directed against CD20/52 antigens. All patients referring to the MS Clinical Care and Research Center, University of Naples "Federico II", who started on alemtuzumab, ocrelizumab or rituximab (off-label use) from 1 November 2015 to 30 June 2019 were recruited. From the 1st of February 2018 patients underwent a microbiological screening and were evaluated by an infectious disease specialist (IDs) before monoclonal antibodies infusion to rule out active infections. We evaluated incidence of infective complications and predictors before (retrospectively)and after (prospectively) the introduction of the above-mentioned anti-infective program. RESULTS: We enrolled 275 patients, 104 retrospectively (pre-intervention group, PRE) and 171 prospectively (post-intervention group, POST). In PRE group, most patients were treated with alemtuzumab (58% vs 32%, p < 0.001), were more frequently DMT naïve (48% vs 36%, p = 0.044) or had received fingolimod in the past (48% vs 28%, p = 0.044) and the follow-up period was longer than in POST group (750 vs 191 days, p < 0.001). In POST group, patients were older (median age 47 vs 42 years, p = 0.030) and mostly received OCR (54% vs 14%, p < 0.001). Lymphopenia at baseline was significantly more commonly observed in PRE arm (47% vs 8%, p < 0.001). A total of 39 patients (38%) in PRE arm and 42 patients (25% in POST) group experienced one or more infections (p = 0.022); severe infections were significantly more common in PRE patients (23% vs 14%, p = 0.022). Our anti-infective program was associated with a lower IAE incidence both at univariate and multivariate analysis (aHR of infective events in PRE group: 3.652 [CI: 9.03-94.19], p < 0.001). Moreover, DMT naïve patients significantly experienced fewer infective complications (aHR: 0.470, [CI: 1.02-2.55], p = 0.040). CONCLUSIONS: A risk mitigation program including infectious disease consultation and standardized screening and prophylactic protocols was effective in reducing infective adverse events in patients receiving anti CD20/CD52 agents for MS.


Asunto(s)
Anticuerpos Monoclonales , Antineoplásicos Inmunológicos , Infecciones , Esclerosis Múltiple , Alemtuzumab/efectos adversos , Alemtuzumab/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antígenos CD20 , Antineoplásicos Inmunológicos/efectos adversos , Antineoplásicos Inmunológicos/uso terapéutico , Antígeno CD52 , Humanos , Infecciones/inducido químicamente , Infecciones/diagnóstico , Persona de Mediana Edad , Esclerosis Múltiple/tratamiento farmacológico , Estudios Prospectivos , Derivación y Consulta , Estudios Retrospectivos , Rituximab/efectos adversos , Rituximab/uso terapéutico
13.
Nanomaterials (Basel) ; 11(10)2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34685157

RESUMEN

Surface decoration by means of metal nanostructures is an effective way to locally modify the electronic properties of materials. The decoration of ZnO nanorods by means of Au nanoparticles was experimentally investigated and modelled in terms of energy band bending. ZnO nanorods were synthesized by chemical bath deposition. Decoration with Au nanoparticles was achieved by immersion in a colloidal solution obtained through the modified Turkevich method. The surface of ZnO nanorods was quantitatively investigated by Scanning Electron Microscopy, Transmission Electron Microscopy and Rutherford Backscattering Spectrometry. The Photoluminescence and Cathodoluminescence of bare and decorated ZnO nanorods were investigated, as well as the band bending through Mott-Schottky electrochemical analyses. Decoration with Au nanoparticles induced a 10 times reduction in free electrons below the surface of ZnO, together with a decrease in UV luminescence and an increase in visible-UV intensity ratio. The effect of decoration was modelled with a nano-Schottky junction at ZnO surface below the Au nanoparticle with a Multiphysics approach. An extensive electric field with a specific halo effect formed beneath the metal-semiconductor interface. ZnO nanorod decoration with Au nanoparticles was shown to be a versatile method to tailor the electronic properties at the semiconductor surface.

14.
Nanomaterials (Basel) ; 10(11)2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33139644

RESUMEN

Decoration of nanostructures is a promising way of improving performances of nanomaterials. In particular, decoration with Au nanoparticles is considerably efficient in sensing and catalysis applications. Here, the mechanism of decoration with Au nanoparticles by means of low-cost electroless deposition (ELD) is investigated on different substrates, demonstrating largely different outcomes. ELD solution with Au potassium cyanide and sodium hypophosphite, at constant temperature (80 °C) and pH (7.5), is used to decorate by immersion metal (Ni) or semiconductor (Si, NiO) substrates, as well as NiO nanowalls. All substrates were pre-treated with a hydrazine hydrate bath. Scanning electron microscopy and Rutherford backscattering spectrometry were used to quantitatively analyze the amount, shape and size of deposited Au. Au nanoparticle decoration by ELD is greatly affected by the substrates, leading to a fast film deposition onto metallic substrate, or to a slow cluster (50-200 nm sized) formation on semiconducting substrate. Size and density of resulting Au clusters strongly depend on substrate material and morphology. Au ELD is shown to proceed through a galvanic displacement on Ni substrate, and it can be modeled with a local cell mechanism widely affected by the substrate conductivity at surface. These data are presented and discussed, allowing for cheap and reproducible Au nanoparticle decoration on several substrates.

15.
Virology ; 540: 57-65, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31739185

RESUMEN

Among the Herpesviridae, human cytomegalovirus (HCMV) owns the largest genome and displays a huge coding potential. Here, we characterized the UL5 gene product (pUL5) of the clinical isolate TR strain. The protein was predicted as a 166-amino-acid membrane protein with a theoretical mass of 19 kDa. Recombinant virus expressing pUL5 with a tag allowed the identification of two pUL5 non-glycosylated species of approximately 19 and 9 kDa, expressed with early and late kinetic respectively. Experiments in infection confirmed that the lower molecular weight species was translated from an internal ATG in the UL5 open reading frame. Confocal microscopy analysis showed that pUL5 localized within the assembly compartment, but is not incorporated in the virion, as shown by Western blot on purified viral particles. Finally, pull-down experiments coupled with mass spectrometry analysis identified IQGAP1 as a pUL5 interactor, giving new hints on possible roles of pUL5 during HCMV infection.


Asunto(s)
Infecciones por Citomegalovirus/metabolismo , Infecciones por Citomegalovirus/virología , Citomegalovirus/fisiología , Interacciones Huésped-Patógeno , Proteínas Virales/metabolismo , Proteínas Activadoras de ras GTPasa/metabolismo , Secuencia de Aminoácidos , Línea Celular , Células Cultivadas , Citomegalovirus/aislamiento & purificación , Citomegalovirus/ultraestructura , Regulación Viral de la Expresión Génica , Humanos , Sistemas de Lectura Abierta , Unión Proteica , Transporte de Proteínas , ARN Viral , Transcripción Genética
16.
Curr Alzheimer Res ; 16(12): 1073-1083, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31642780

RESUMEN

BACKGROUND: Life expectancy is increasing all over the world, although neurodegenerative disorders might drastically affect the individual activity of aged people. Of those, Alzheimer's Disease (AD) is one of the most social-cost age-linked diseases of industrialized countries. To date, retinal diseases seem to be more common in the developing world and characterize principally aged people. Agerelated Macular Degeneration (AMD) is a late-onset, neurodegenerative retinal disease that shares several clinical and pathological features with AD, including stress stimuli such as oxidative stress, inflammation and amyloid formations. METHODS: In both diseases, the detrimental intra/extra-cellular deposits have many similarities. Aging, hypercholesterolemia, hypertension, obesity, arteriosclerosis and smoking are risk factors to develop both diseases. Cellular aging routes have similar organelle and signaling patterns in retina and brain. The possibility to find out new research strategies represent a step forward to disclose potential treatment for both of them. Essential trace metals play critical roles in both physiological and pathological condition of retina, optic nerve and brain, by influencing metabolic processes chiefly upon complex multifactorial pathogenesis. CONCLUSION: Hence, this review addresses current knowledge about some up-to-date investigated essential trace metals associated with AD and AMD. Changes in the levels of systemic and ocular fluid essential metals might reflect the early stages of AMD, possibly disclosing neurodegeneration pathways shared with AD, which might open to potential early detection.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Humor Acuoso/metabolismo , Degeneración Retiniana/metabolismo , Oligoelementos/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Animales , Humor Acuoso/química , Humor Acuoso/diagnóstico por imagen , Humanos , Degeneración Macular/diagnóstico por imagen , Degeneración Macular/metabolismo , Estrés Oxidativo/fisiología , Degeneración Retiniana/diagnóstico por imagen , Distribución Tisular/fisiología , Oligoelementos/análisis
17.
PLoS One ; 14(11): e0224982, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31725734

RESUMEN

PURPOSE: To evaluate the presence and concentration of citicoline and its metabolites (choline, cytidine and uridine) in the vitreous body in human eyes after topical application of an ophthalmic solution of citicoline 2%, in vivo. METHODS: Twenty-one subjects affected by epiretinal membrane with surgical indication for pars-plana vitrectomy underwent treatment with 1 drop 3 times/day of a solution of citicoline 2%, 0.2% high molecular weight hyaluronic acid and 0.01% benzalkonium chloride (OMK1, Omikron Italia s.r.l., Rome, Italy) 14 days before surgery and 2 hours prior to surgery. Five additional patients served as controls and received an OMK1 vehicle solution without citicoline. The vitreous samples were taken at the beginning of the pars-plana vitrectomy and analyzed for qualitative/quantitative determination of vitreous concentration of citicoline and its metabolites by means of high performance liquid chromatography. RESULTS: The overall mean concentration of citicoline in patients treated with citicoline 2% solution was 406.72 ± 52.99 µg/mL, while the mean concentration of choline, cytidine and uridine was 180.88 ± 41.49 µg/mL, 44.45 ± 10.19 µg/mL and 330.41 ± 75.8 µg/mL, respectively. The concentration of citicoline in phakic eyes (n = 13, 366.61 ± 129.61 µg/mL) was lower compared to that found in pseudophakic eyes (n = 8, 435.89 ± 131.42 µg/mL) and the difference was not statistically significant. The concentration of citicoline in the control eyes was 45.66 ± 26.36 µg/mL, while the concentration of choline, cytidine and uridine were 17.21 ± 9.93 µg/mL, 6.24 ± 3.6 µg/mL and 172.80 ± 99.76 µg/mL, respectively. CONCLUSION: Citicoline can reach the human vitreous in high concentration when administered in ophthalmic solution. This evidence contributes to the build-up of the pyramid of the evidences required for determining the role of citicoline administered in ophthalmic formulation in retinal and optic nerve neurodegenerative diseases.


Asunto(s)
Citidina Difosfato Colina/administración & dosificación , Soluciones Oftálmicas/administración & dosificación , Anciano , Cromatografía Líquida de Alta Presión , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Soluciones Oftálmicas/química
18.
Radiat Prot Dosimetry ; 164(1-2): 112-5, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25377753

RESUMEN

The European Laboratory for Particle Physics (CERN) has operated high-energy accelerators for fundamental physics research for nearly 60 y. The side-product of this activity is the radioactive waste, which is mainly generated as a result of preventive and corrective maintenance, upgrading activities and the dismantling of experiments or accelerator facilities. Prior to treatment and disposal, it is common practice to temporarily store radioactive waste on CERN's premises and it is a legal requirement that these storage facilities are safe and secure. Waste treatment typically includes sorting, segregation, volume and size reduction and packaging, which will depend on the type of component, its chemical composition, residual activity and possible surface contamination. At CERN, these activities are performed in a dedicated waste treatment centre under the supervision of the Radiation Protection Group. This paper gives an overview of the radiation protection challenges in the conception of a temporary storage and treatment centre for radioactive waste in an accelerator facility, based on the experience gained at CERN. The CERN approach consists of the classification of waste items into 'families' with similar radiological and physical-chemical properties. This classification allows the use of specific, family-dependent techniques for radiological characterisation and treatment, which are simultaneously efficient and compliant with best practices in radiation protection. The storage was planned on the basis of radiological and other possible hazards such as toxicity, pollution and fire load. Examples are given of technical choices for the treatment and radiological characterisation of selected waste families, which could be of interest to other accelerator facilities.


Asunto(s)
Aceleradores de Partículas , Monitoreo de Radiación/métodos , Protección Radiológica/métodos , Residuos Radiactivos/prevención & control , Administración de la Seguridad/organización & administración , Administración de Residuos/métodos , Residuos Radiactivos/análisis , Eliminación de Residuos/métodos , Suiza
19.
Curr Opin Virol ; 11: 89-97, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25829256

RESUMEN

Although almost 15 years have passed since the birthdate of Reverse Vaccinology (RV), there are very limited applications of this approach to viral vaccines discovery. Undeniably, RV presents a series of advantages as it can virtually identify all potential antigens coded by a genome, irrespective of their abundance, phase of expression and immunogenicity. Additionally, it can be applied to all pathogens, including those that cannot be grown in vitro. In this review we summarize the few examples of RV application to viruses, in particular the Herpesviridae, and report the advantage and limitations of this approach. Next we focus on the novel approaches and additional technologies to vaccine development including structure based approach (Structural Vaccinology [SV]), synthetic biology and some examples of their application in the development of viral vaccines.


Asunto(s)
Herpesviridae/genética , Herpesviridae/inmunología , Vacunas contra Herpesvirus/inmunología , Vacunas contra Herpesvirus/aislamiento & purificación , Genética Inversa/métodos , Descubrimiento de Drogas/métodos , Vacunas contra Herpesvirus/genética , Humanos
20.
Phys Life Rev ; 6(3): 176-206, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20416851

RESUMEN

This paper aims to provide a review and critical analysis of the state of the art concerning crowd-structure interaction phenomena on footbridges. The problem of lateral vibrations induced by synchronised pedestrians, namely the Synchronous Lateral Excitation, is specifically addressed. Due to the multi-physic and multi-scale nature of the complex phenomenon, several research fields can contribute to its study, from structural engineering to biomechanics, from transportation engineering to physics and applied mathematics. The different components of the overall coupled dynamical system - the structure, the crowd and their interactions - are separately analysed from both a phenomenological and modelling point of view. A special attention is devoted to those models, which explicitly account for the interaction between mechanical and living systems.

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