1,161 research outputs found

    Hyaluronic acid—dexamethasone nanoparticles for local adjunct therapy of lung inflammation

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    The delivery of a dexamethasone formulation directly into the lung appears as an appro-priate strategy to strengthen the systemic administration, reducing the dosage in the treatment of lung severe inflammations. For this purpose, a hyaluronic acid-dexamethasone formulation was developed, affording an inhalable reconstituted nanosuspension suitable to be aerosolized. The physico-chemical and biopharmaceutical properties of the formulation were tested: size, stability, loading of the spray-dried dry powder, reconstitution capability upon redispersion in aqueous me-dia. Detailed structural insights on nanoparticles after reconstitution were obtained by light and X-ray scattering techniques. (1) The size of the nanoparticles, around 200 nm, is in the proper range for a possible engulfment by macrophages. (2) Their structure is of the core-shell type, hosting dex-amethasone nanocrystals inside and carrying hyaluronic acid chains on the surface. This specific structure allows for nanosuspension stability and provides nanoparticles with muco-inert proper-ties. (3) The nanosuspension can be efficiently aerosolized, allowing for a high drug fraction poten-tially reaching the deep lung. Thus, this formulation represents a promising tool for the lung administration via nebulization directly in the pipe of ventilators, to be used as such or as adjunct therapy for severe lung inflammation.Fil: CĂĄmara, Candelaria InĂ©s. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones en FĂ­sico-quĂ­mica de CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Instituto de Investigaciones en FĂ­sico-quĂ­mica de CĂłrdoba; ArgentinaFil: Bertocchi, Laura. Departamento de Alimentos y Drogas ; Universita Degli Studi Di Parma;Fil: Ricci, Caterina. Universita Degli Studi Di Milano. Dipartimento Di Beitecnologe Mediche E Medicina Traslazionale.; ItaliaFil: Bassi, Rosaria. Universita Degli Studi Di Milano. Dipartimento Di Beitecnologe Mediche E Medicina Traslazionale.; ItaliaFil: Bianchera, Annalisa. Departamento de Alimentos y Drogas ; Universita Degli Studi Di Parma;Fil: CantĂș, Laura F.. Universita Degli Studi Di Milano. Dipartimento Di Beitecnologe Mediche E Medicina Traslazionale.; ItaliaFil: Ruggero, Bettini. Departamento de Alimentos y Drogas ; Universita Degli Studi Di Parma;Fil: Del Favero, Elena. Universita Degli Studi Di Milano. Dipartimento Di Beitecnologe Mediche E Medicina Traslazionale.; Itali

    Vestendo l'abito religioso dell'umiltĂ  della beatissima Vergine di Parigi nel nobilissimo munistero delle reverende madri de SS. Lodovico, et Alessio di Bologna sotto la regola di Santa Chiara la molto illustre signora Anna Maria Margarita Sandelli col assumere li nomi di suor Maria Ildegarde Francesca Chiara Gioseffa / [L.M.C.B.

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    1 foglio ; 44x57 cm Probabile nome dell'A., Laura Maria Caterina Bassi Fregi e iniziali xilogr Testo stampato su due colonne

    Time-resolved optical spectrometer based on a monolithic array of high-precision TDCs and SPADs

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    We present a compact time-resolved spectrometer suitable for optical spectroscopy from 400 nm to 1 ÎŒm wavelengths. The detector consists of a monolithic array of 16 high-precision Time-to-Digital Converters (TDC) and Single-Photon Avalanche Diodes (SPAD). The instrument has 10 ps resolution and reaches 70 ps (FWHM) timing precision over a 160 ns full-scale range with a Differential Non-Linearity (DNL) better than 1.5 % LSB. The core of the spectrometer is the application-specific integrated chip composed of 16 pixels with 250 ÎŒm pitch, containing a 20 ÎŒm diameter SPAD and an independent TDC each, fabricated in a 0.35 ÎŒm CMOS technology. In front of this array a monochromator is used to focus different wavelengths into different pixels. The spectrometer has been used for fluorescence lifetime spectroscopy: 5 nm spectral resolution over an 80 nm bandwidth is achieved. Lifetime spectroscopy of Nile blue is demonstrated

    Effects of thoraco-pelvic supports during prone position in patients with acute lung injury/acute respiratory distress syndrome: a physiological study

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    INTRODUCTION: This study sought to assess whether the use of thoraco-pelvic supports during prone positioning in patients with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) improves, deteriorates or leaves unmodified gas exchange, hemodynamics and respiratory mechanics. METHODS: We studied 11 patients with ALI/ARDS, sedated and paralyzed, mechanically ventilated in volume control ventilation. Prone positioning with or without thoraco-pelvic supports was applied in a random sequence and maintained for a 1-hour period without changing the ventilation setting. In four healthy subjects the pressures between the body and the contact surface were measured with and without thoraco-pelvic supports. Oxygenation variables (arterial and central venous), physiologic dead space, end-expiratory lung volume (helium dilution technique) and respiratory mechanics (partitioned between lung and chest wall) were measured after 60 minutes in each condition. RESULTS: With thoraco-pelvic supports, the contact pressures almost doubled in comparison with those measured without supports (19.1 ± 15.2 versus 10.8 ± 7.0 cmH(2)O, p ≀ 0.05; means ± SD). The oxygenation-related variables were not different in the prone position, with or without thoraco-pelvic supports; neither were the CO(2)-related variables. The lung volumes were similar in the prone position with and without thoraco-pelvic supports. The use of thoraco-pelvic supports, however, did lead to a significant decrease in chest wall compliance from 158.1 ± 77.8 to 102.5 ± 38.0 ml/cmH(2)O and a significantly increased pleural pressure from 4.3 ± 1.9 to 6.1 ± 1.8 cmH(2)O, in comparison with the prone position without supports. Moreover, when thoraco-pelvic supports were added, heart rate increased significantly from 82.1 ± 17.9 to 86.7 ± 16.7 beats/minute and stroke volume index decreased significantly from 37.8 ± 6.8 to 34.9 ± 5.4 ml/m(2). The increase in pleural pressure change was associated with a significant increase in heart rate (p = 0.0003) and decrease in stroke volume index (p = 0.0241). CONCLUSION: The application of thoraco-pelvic supports decreases chest wall compliance, increases pleural pressure and slightly deteriorates hemodynamics without any advantage in gas exchange. Consequently, we stopped their use in clinical practice

    A Surface Plasmon Resonance Plastic Optical Fiber Biosensor for the Detection of Pancreatic Amylase in Surgically-Placed Drain Effluent

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    Postoperative pancreatic fistula (POPF), the major driver of morbidity and mortality following pancreatectomy, is caused by an abnormal communication between the pancreatic ductal epithelium and another epithelial surface containing pancreas-derived, enzyme-rich fluid. There is a strong correlation between the amylase content in surgically-placed drains early in the postoperative course and the development of POPF. A simple and cheap method to determine the amylase content from the drain effluent has been eagerly advocated. Here, we developed an amylase optical biosensor, based on a surface plasmon resonance (SPR) plastic optical fiber (POF), metallized with a 60 nm layer of gold and interrogated with white light. The sensor was made specific by coupling it with an anti-amylase antibody. Each surface derivatization step was optimized and studied by XPS, contact angle, and fluorescence. The POF-biosensor was tested for its response to amylase in diluted drain effluents. The volume of sample required was 50 \ub5L and the measurement time was 8 min. The POF-biosensor showed selectivity for amylase, a calibration curve log-linear in the range of 0.8\u201325.8 U/L and a limit of detection (LOD) of ~0.5 U/L. In preliminary tests, the POF-biosensor allowed for the measurement of the amylase content of diluted surgically-placed drain effluents with an accuracy of >92% with respect to the gold standard. The POF-biosensor allows for reliable measurement and could be implemented to allow for a rapid bedside assessment of amylase value in drains following pancreatectomy

    Cerebellar haemorrhages and pons development in extremely low birth weight infants.

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    UNLABELLED Neuropathological and Magnetic Resonance Imaging (MRI) studies showed a high frequency of posterior fossa abnormalities in preterms. To assess whether cerebellar haemorrhages (CH) diagnosed with ultrasound and/or MRI affect pons development in ELBW infants. The anteroposterior diameter of the pons was measured manually on the midline sagittal T1 MR image in 75 ELBW babies consecutively scanned at term postmenstrual age. Subjects with CH were identified and compared to babies with no posterior fossa bleeding. Nine ELBW infants with CH (CH-Group: median gestational age -GA- 26 wks, range 23-27; birth weight -BW- 680 g, 425-980) were compared with 66 babies with normal cerebellum (Control-Group: GA 28 wks, 23-33; BW 815 g, 430-1000). The two groups were comparable for BW (p=0.088) while GA was significantly shorter in CH babies (p=0.005). The pontine diameter was significantly lower in CH-Group compared to Control-Group (12.8 +/- 2.2 vs 14.8 +/- 1.2 mm; p<0.001). CONCLUSIONS Cerebellar haemorrhages seem to affect the development of the pons in ELBW with the youngest GA

    Fluorescent Carbon Dots from Food Industry By-Products for Cell Imaging

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    Herein, following a circular economy approach, we present the synthesis of luminescent carbon dots via the thermal treatment of chestnut and peanut shells, which are abundant carbon-rich food industry by-products. As-synthesized carbon dots have excellent water dispersibility thanks to their negative surface groups, good luminescence, and photo-stability. The excitation-emission behaviour as well as the surface functionalization of these carbon dots can be tuned by changing the carbon source (chestnuts or peanuts) and the dispersing medium (water or ammonium hydroxide solution). Preliminary in vitro biological data proved that the samples are not cytotoxic to fibroblasts and can act as luminescent probes for cellular imaging. In addition, these carbon dots have a pH-dependent luminescence and may, therefore, serve as cellular pH sensors. This work paves the way towards the development of more sustainable carbon dot production for biomedical applications

    miR-221 affects multiple cancer pathways by modulating the level of hundreds messenger RNAs.

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    microRNA miR-221 is frequently over-expressed in a variety of human neoplasms. Aim of this study was to identify new miR-221 gene targets to improve our understanding on the molecular tumor-promoting mechanisms affected by miR-221. Gene expression profiling of miR-221-transfected-SNU-398 cells was analyzed by the Sylamer algorithm to verify the enrichment of miR-221 targets among down-modulated genes. This analysis revealed that enforced expression of miR-221 in SNU-398 cells caused the down-regulation of 602 mRNAs carrying sequences homologous to miR-221 seed sequence within their 3'UTRs. Pathways analysis performed on these genes revealed their prominent involvement in cell proliferation and apoptosis. Activation of E2F, MYC, NFkB, and ÎČ-catenin pathways was experimentally proven. Some of the new miR-221 target genes, including RB1, WEE1 (cell cycle inhibitors), APAF1 (pro-apoptotic), ANXA1, CTCF (transcriptional repressor), were individually validated as miR-221 targets in SNU-398, HepG2, and HEK293 cell lines. By identifying a large set of miR-221 gene targets, this study improves our knowledge about miR-221 molecular mechanisms involved in tumorigenesis. The modulation of mRNA level of 602 genes confirms the ability of miR-221 to promote cancer by affecting multiple oncogenic pathways
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