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1.
Artigo em Inglês | MEDLINE | ID: mdl-38866395

RESUMO

BACKGROUND AND AIM: Pelvic inflammatory disease (PID) is usually managed by conservative treatment, but in selected cases, especially in the presence of a tubo-ovarian abscess (TOA), surgical management is a recognized treatment option. We compared the trends in managing PID and short-term outcomes before and during the SARS-CoV-2 pandemic. METHODS: This is a retrospective study performed in three Italian gynecological centers. We included patients admitted to hospital with a diagnosis of PID. Demographic characteristics, management, time to diagnosis, and time to treatment were compared before versus during the SARS-CoV-2 pandemic. RESULTS: One hundred nineteen PID patients were screened, eighty-one before the SARS-CoV-2 pandemic, and thirty-eight after the onset. At admission, leukocytosis (median 19.73 vs. 13.99 WBC/mm3, p-value = 0.02) was significantly higher in patients who underwent surgery after the onset of the pandemic. TOA incidence was higher in patients who underwent surgery during the SARS-CoV-2 pandemic, but the difference did not reach statistically significance (p = 0.06). The proportion of patients treated with surgery dropped to 26.3% after the onset from 46% of patients before the onset of pandemic (p = 0.03). Furthermore, a higher percentage of emergency surgical procedures on day 0 of hospital admission were performed after the onset of the pandemic (50% vs. 13.1%, p = 0.01). CONCLUSIONS: In this retrospective cohort study, we found that the SARS-CoV-2 pandemic influenced the clinical presentation and management of PID in favor of conservative treatment. Patients who underwent surgery during the SARS-CoV-2 pandemic had higher inflammatory markers.

2.
Phys Chem Chem Phys ; 24(4): 2349-2356, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35018905

RESUMO

By employing diverse surface sensitive synchrotron radiation spectroscopies we demonstrate that the fluorine content of initial C60F48 deposited at room temperature on Ag(111) varies with molecular coverage. At the very early stages of deposition, C60F48 fully de-fluorinates and transforms into C60. Strong indications of silver fluoride formation are provided. The chemical footprint of fluorinated fullerenes emerges at relatively low molecular coverage indicating that the degree of fullerene de-fluorination decreases (from total to partial de-fluorination) as molecules are deposited. Full de-fluorination stops well before the substrate surface is completely covered by fullerenes. At the molecular level, the fluorine loss observed by spectroscopic techniques is supported by scanning tunneling microscopy imaging. Both molecules and metal surface are importantly involved in the process.

3.
Opt Express ; 20(23): 25267-74, 2012 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-23187343

RESUMO

We have fabricated and characterized fully programmable diffraction gratings consisting of 64 silicon micro-mirrors. The mirrors are 700µm long and 50µm wide with a fill factor of 90%. They are actuated electrostatically and move down by 1.25µm while showing negligible cross-talk and bowing as small as 0.14µm over 700µm. Extinction ratio up to 100 has been achieved by adjusting only 3 adjacent micro-mirrors. The gratings could operate either as light modulators up to 5µm or spectra generators up to 2.5µm.

4.
Nanotechnology ; 22(18): 185305, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21427473

RESUMO

Ordered arrays of nanoelectrodes for electrochemical use are prepared by electron beam lithography (EBL) using polycarbonate as a novel e-beam resist. The nanoelectrodes are fabricated by patterning arrays of holes in a thin film of polycarbonate spin-coated on a gold layer on Si/Si(3)N(4) substrate. Experimental parameters for the successful use of polycarbonate as high resolution EBL resist are optimized. The holes can be filled partially or completely by electrochemical deposition of gold. This enables the preparation of arrays of nanoelectrodes with different recession degree and geometrical characteristics. The polycarbonate is kept on-site and used as the insulator that separates the nanoelectrodes. The obtained nanoelectrode arrays (NEAs) exhibit steady state current controlled by pure radial diffusion in cyclic voltammetry for scan rates up to approximately 50 mV s( - 1). Electrochemical results showed satisfactory agreement between experimental voltammograms and suitable theoretical models. Finally, the peculiarities of NEAs versus ensembles of nanoelectrodes, obtained by membrane template synthesis, are critically evaluated.

5.
Biosens Bioelectron ; 23(12): 1900-3, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18407487

RESUMO

In this study we demonstrate the possibility to prepare highly sensitive nanostructured electrochemical immunosensors by immobilizing biorecognition elements on nanoelectrode ensembles (NEEs) prepared in track-etch polycarbonate membranes. The gold nanodisk electrodes act as electrochemical transducers while the surrounding polycarbonate binds the antibody-based biorecognition layer. The interaction between target protein and antibody is detected by suitable secondary antibodies labelled with a redox enzyme. A redox mediator, added to the sample solution, shuttles electrons from the nanoelectrodes to the biorecognition layer, so generating an electrocatalytic signal. This allows one to fully exploit the highly improved signal-to-background current ratio, typical of NEEs. In particular, the receptor protein HER2 was studied as the target analyte. HER2 detection allows the identification of breast cancer that can be treated with the monoclonal antibody trastuzumab. NEEs were functionalized with trastuzumab which interacts specifically with HER2. The biorecognition process was completed by adding a primary antibody and a secondary antibody labelled with horseradish peroxidase. Hydrogen peroxide was added to modulate the label electroactivity; methylene blue was the redox mediator generating voltammetric signals. NEEs functionalized with trastuzumab were tested to detect small amounts of HER2 in diluted cell lysates and tumour lysates.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Imunoensaio/instrumentação , Microeletrodos , Nanotecnologia/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento
6.
Nanotechnology ; 19(44): 445502, 2008 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21832731

RESUMO

Mechanical oscillators became a main focus of research in recent years for potential applications in biomolecule detectors. We recently demonstrated the feasibility of a scheme based on twin cantilevers with a sensitivity down to the single molecule. This approach is extremely promising under the condition that the two terminals of the device can be functionalized with high selectivity and nanometric accuracy by linker molecules. Here we demonstrate a chemo-mechanical method to achieve the intrinsically aligned functionalization of two silicon surfaces, which can be separated by a gap controllable with nanometric precision. The chemical binding of the target molecules in the selected position is obtained through a cycloaddition reaction which exploits the reactivity of the freshly cleaved surfaces that form when the cantilever gap is created. The general validity of this approach is shown by the use in different chemical environments of two compounds with different reactive functional groups.

7.
J Biomed Mater Res A ; 83(4): 965-969, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17580325

RESUMO

Transplantation of encapsulated pancreatic islets is a promising approach for the treatment of type 1 diabetes. Large-scale application of this technique, however, is hampered by insufficient biocompatibility of the capsules. In this study, we have evaluated the biocompatibility of a new synthetic material with six different chemical groups on their surface (amino, carboxy-sulfate, carboxylate, hydroxylate, sulfate, and PMMA) used for the fabrication of the microcapsules. Eight Lewis rats were inoculated with a suspension of empty capsules made for each candidate material in the retroperitoneal ileopsoas muscle and renal subcapsular space. Four weeks later kidney and muscle containing the capsules were explanted, paraffin embedded, sectioned and stained with Sirius Red and Masson's Trichrome for histological analysis. The amount of fibrosis was also ultrastructurally evaluated with scanning electron microscopy. The samples were then subjected to digitalized quantitative analysis using specific software to determine the degree of fibrotic overgrowth. The quantification of collagen deposition, calculated in proximity of the microcapsules, was expressed as a percentage of the total area and can be considered a good index for the biocompatibility, an essential prerequisite for functional pancreatic islet transplantation. The results show that subcapsular renal space is the best implantation site and the positive surface charge induces a more intense collagen synthesis.


Assuntos
Fibrose , Transplante das Ilhotas Pancreáticas , Animais , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/terapia , Masculino , Ratos , Ratos Endogâmicos Lew , Propriedades de Superfície
8.
Nanomedicine (Lond) ; 1(3): 281-96, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17716159

RESUMO

This review discusses some of the most common polymer scaffold fabrication techniques used for tissue engineering applications. Although the field of scaffold fabrication is now well established and advancing at a fast rate, more progress remains to be made, especially in engineering small diameter blood vessels and providing scaffolds that can support deep tissue structures. With this in mind, we introduce two new lithographic methods that we expect to go some way to addressing this problem.


Assuntos
Materiais Biocompatíveis/química , Vasos Sanguíneos/crescimento & desenvolvimento , Polímeros/química , Engenharia Tecidual/métodos , Animais , Vasos Sanguíneos/química , Humanos , Modelos Teóricos , Nanotecnologia/métodos , Engenharia Tecidual/instrumentação
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