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1.
World Neurosurg X ; 18: 100162, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36818735

RESUMO

Background: Vertebral arthrodesis for degenerative pathology of the lumbar spine still remains burdened by clinical problems with significant negative results. The introduction of the sagittal balance assessment with the evaluation of the meaning of pelvic parameters and spinopelvic (PI-LL) mismatch offered new evaluation criteria for this widespread pathology, but there is a lack of consistent evidence on long-term outcome. Methods: The authors performed an extensive systematic review of literature, with the aim to identify all potentially relevant studies about the role and usefulness of the restoration or the assessment of Sagittal balance in lumbar degenerative disease. They present the study protocol RELApSE (NCT05448092 ID) and discuss the rationale through a comprehensive literature review. Results: From the 237 papers on this topic, a total of 176 articles were selected in this review. The analysis of these literature data shows sparse and variable evidence. There are no observations or guidelines about the value of lordosis restoration or PI-LL mismatch. Most of the works in the literature are retrospective, monocentric, based on small populations, and often address the topic evaluation partially. Conclusions: The RELApSE study is based on the possibility of comparing a heterogeneous population by pathology and different surgical technical options on some homogeneous clinical and anatomic-radiological measures aiming to understanding the value that global lumbar and segmental lordosis, distribution of lordosis, pelvic tilt, and PI-LL mismatch may have on clinical outcome in lumbar degenerative pathology and on the occurrence of adjacent segment disease.

2.
Gels ; 8(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36135306

RESUMO

Gelatin is a popular biopolymer for biomedical applications due to its harmless impact with a negligible inflammatory response in the host organism. Gelatin interacts with soluble molecules in aqueous media as ionic counterparts such as ionic liquids (ILs) to be used as cosolvents to generate the so-called Ionogels. The perfluorinated IL (FIL), 1-ethyl-3-methylpyridinium perfluorobutanesulfonate, has been selected as co-hydrosolvent for fish gelatin due to its low cytotoxicity and hydrophobicity aprotic polar structure to improve the drug aqueous solubility. A series of FIL/water emulsions with different FIL content and their corresponding shark gelatin/FIL Ionogel has been designed to enhance the drug solubility whilst retaining the mechanical structure and their nanostructure was probed by simultaneous SAXS/WAXS, FTIR and Raman spectroscopy, DSC and rheological experiments. Likewise, the FIL assisted the solubility of the antitumoural Doxorubicin whilst retaining the performing mechanical properties of the drug delivery system network for the drug storage as well as the local administration by a syringe. In addition, the different controlled release mechanisms of two different antitumoral such as Doxorubicin and Mithramycin from two different Ionogels formulations were compared to previous gelatin hydrogels which proved the key structure correlation required to attain specific therapeutic dosages.

3.
Pharmaceutics ; 14(6)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35745711

RESUMO

A series of bionanocomposites composed of shark gelatin hydrogels and PLA nanoparticles featuring different nanostructures were designed to generate multifunctional drug delivery systems with tailored release rates required for personalized treatment approaches. The global conception of the systems was considered from the desired customization of the drug release while featuring the viscoelastic properties needed for their ease of storage and posterior local administration as well as their biocompatibility and cell growth capability for the successful administration at the biomolecular level. The hydrogel matrix offers the support to develop a direct thermal method to convert the typical kinetic trapped nanostructures afforded by the formulation method whilst avoiding the detrimental nanoparticle agglomeration that diminishes their therapeutic effect. The nanoparticles generated were successfully formulated with two different antitumoral compounds (doxorubicin and dasatinib) possessing different structures to prove the loading versatility of the drug delivery system. The bionanocomposites were characterized by several techniques (SEM, DLS, RAMAN, DSC, SAXS/WAXS and rheology) as well as their reversible sol-gel transition upon thermal treatment that occurs during the drug delivery system preparation and the thermal annealing step. In addition, the local applicability of the drug delivery system was assessed by the so-called "syringe test" to validate both the storage capability and its flow properties at simulated physiological conditions. Finally, the drug release profiles of the doxorubicin from both the PLA nanoparticles or the bionanocomposites were analyzed and correlated to the nanostructure of the drug delivery system.

4.
Gels ; 8(4)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35448138

RESUMO

The skin of yellowfin tuna is one of the fishery industry solid residues with the greatest potential to add extra value to its circular economy that remains yet unexploited. Particularly, the high collagen content of fish skin allows generating gelatin by hydrolysis, which is ideal for forming hydrogels due to its biocompatibility and gelling capability. Hydrogels have been used as drug carriers for local administration due to their mechanical properties and drug loading capacity. Herein, novel tuna gelatin hydrogels were designed as drug vehicles with two structurally different antitumoral model compounds such as Doxorubicin and Crocin to be administrated locally in tissues with complex human anatomies after surgical resection. The characterization by gel permeation chromatography (GPC) of purified gelatin confirmed their heterogeneity composition, exhibiting three major bands that correspond to the ß and α chains along with high molecular weight species. In addition, the Fourier Transform Infrared (FT-IR) spectra of gelatin probed the secondary structure of the gelatin showing the simultaneous existence of α helix, ß sheet, and random coil structures. Morphological studies at different length scales were performed by a multi-technique approach using SAXS/WAXS, AFM and cryo-SEM that revealed the porous network formed by the interaction of gelatin planar aggregates. In addition, the sol-gel transition, as well as the gelation point and the hydrogel strength, were studied using dynamic rheology and differential scanning calorimetry. Likewise, the loading and release profiles followed by UV-visible spectroscopy indicated that the novel gelatin hydrogels improve the drug release of Doxorubicin and Crocin in a sustained fashion, indicating the structure-function importance in the material composition.

5.
Anal Chem ; 93(44): 14651-14658, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34698490

RESUMO

The nondestructive investigation of millimeter-sized meteoritic materials is often hindered by self-absorption effects. Using X-ray-based analytical methods, the information depth for many elements (Z < 30) is in the range of up to only a few hundred micrometers, and for low-Z elements (Z < 20), this is reduced even further to only a few tens of micrometers. However, the investigation of these low-Z elements, in particular calcium, aluminum, and magnesium, is of great importance to planetary geologists and cosmochemists, as these elements are regularly used to characterize and identify specific features of interest in extraterrestrial materials, especially primitive chondritic material. In this work, nonresonant inelastic X-ray scattering from core electrons was performed at beamline ID20 of the ESRF in a direct tomography approach in order to visualize these low-Z elements within the millimeter-sized meteoritic samples. The obtained 3D elemental distribution volumes were compared to results from X-ray fluorescence-CT and absorption CT experiments and were found to be in good agreement. Additionally, several regions of interest could be identified within the inelastic scattering volumes, containing information that is not available through the other presented means. As such, the proposed approach presents a valuable tool for the nondestructive investigation of low-Z elemental distributions within millimeter-sized extraterrestrial materials, such as the samples of the Hayabusa2 sample return mission.

6.
Front Surg ; 8: 657901, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859995

RESUMO

Background: While performing surgeries in the OR, surgeons and assistants often need to access several information regarding surgical planning and/or procedures related to the surgery itself, or the accessory equipment to perform certain operations. The accessibility of this information often relies on the physical presence of technical and medical specialists in the OR, which is increasingly difficult due to the number of limitations imposed by the COVID emergency to avoid overcrowded environments or external personnel. Here, we analyze several scenarios where we equipped OR personnel with augmented reality (AR) glasses, allowing a remote specialist to guide OR operations through voice and ad-hoc visuals, superimposed to the field of view of the operator wearing them. Methods: This study is a preliminary case series of prospective collected data about the use of AR-assistance in spine surgery from January to July 2020. The technology has been used on a cohort of 12 patients affected by degenerative lumbar spine disease with lumbar sciatica co-morbidities. Surgeons and OR specialists were equipped with AR devices, customized with P2P videoconference commercial apps, or customized holographic apps. The devices were tested during surgeries for lumbar arthrodesis in a multicenter experience involving author's Institutions. Findings: A total number of 12 lumbar arthrodesis have been performed while using the described AR technology, with application spanning from telementoring (3), teaching (2), surgical planning superimposition and interaction with the hologram using a custom application for Microsoft hololens (1). Surgeons wearing the AR goggles reported a positive feedback as for the ergonomy, wearability and comfort during the procedure; being able to visualize a 3D reconstruction during surgery was perceived as a straightforward benefit, allowing to speed-up procedures, thus limiting post-operational complications. The possibility of remotely interacting with a specialist on the glasses was a potent added value during COVID emergency, due to limited access of non-resident personnel in the OR. Interpretation: By allowing surgeons to overlay digital medical content on actual surroundings, augmented reality surgery can be exploited easily in multiple scenarios by adapting commercially available or custom-made apps to several use cases. The possibility to observe directly the operatory theater through the eyes of the surgeon might be a game-changer, giving the chance to unexperienced surgeons to be virtually at the site of the operation, or allowing a remote experienced operator to guide wisely the unexperienced surgeon during a procedure.

7.
Biophys J ; 120(5): 886-898, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33545104

RESUMO

Protein aggregation is a widespread process leading to deleterious consequences in the organism, with amyloid aggregates being important not only in biology but also for drug design and biomaterial production. Insulin is a protein largely used in diabetes treatment, and its amyloid aggregation is at the basis of the so-called insulin-derived amyloidosis. Here, we uncover the major role of zinc in both insulin dynamics and aggregation kinetics at low pH, in which the formation of different amyloid superstructures (fibrils and spherulites) can be thermally induced. Amyloid aggregation is accompanied by zinc release and the suppression of water-sustained insulin dynamics, as shown by particle-induced x-ray emission and x-ray absorption spectroscopy and by neutron spectroscopy, respectively. Our study shows that zinc binding stabilizes the native form of insulin by facilitating hydration of this hydrophobic protein and suggests that introducing new binding sites for zinc can improve insulin stability and tune its aggregation propensity.


Assuntos
Amiloide , Zinco , Humanos , Insulina , Cinética , Espectroscopia por Absorção de Raios X
8.
Data Brief ; 24: 103954, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31193062

RESUMO

We report the series of Pd K-edge X-ray absorption spectra collected during hydrogenation of ethylene with variable ethylene/hydrogen ratio over carbon supported palladium nanoparticles. The data presented in this article includes normalized X-ray absorption spectra, k 2-weighted oscillatory χ(k) functions extracted from the extended X-ray absorption fine structure (EXAFS) and k 2-weighted Fourier-transformed EXAFS data, χ(R). Each spectrum is reported together with the hydrogen, ethylene and helium flow rates, adjusted during its collection. In addition, time evolution of the ratio of m/Z signals of 30 and 28 registered by online mass spectrometer is presented. The data analysis is reported in Bugaev et al., Catal. Today, 2019 [1].

9.
Appl Radiat Isot ; 148: 160-167, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30959353

RESUMO

The activity concentrations of beryllium-7, a natural radiotracer that is considered as a tracer of the stratospheric-tropospheric exchange, shows a distinct behaviour in Northern Europe compared to the central and southern parts of the continent. In this study, we use the measurements collected at four sampling stations in Scandinavia (Ivalo, Umea, Kista, Risoe) between 2001 and 2010 and investigate their trends, periodicities and residuals with the aim to further understand the common features in the beryllium-7 data records in northern sampling sites. The beryllium-7 activity concentrations exhibit statistically significant positive trends that range from an average value of 1.50%/year to an average value of 2.96%/year. We detect a one-year periodicity in all the sites, and in the southernmost site, Risoe in Denmark, additional higher-frequency harmonics. In the residual time series, we find outliers that represent occurrences of extremely high beryllium-7 activity concentration. Cross-correlations of the beryllium-7 residuals across the four sites decrease with increasing distance; similarly, as indicated by local Hurst exponents the records exhibit long-range correlations that weaken towards the end of the investigated period. To investigate the causes of the detected trends, we also calculate correlations between beryllium-7 and factors related to its production, transport and removal from the atmosphere: in particular, cross-correlations of the beryllium-7 residuals with residuals in sunspot number, local temperature, atmospheric pressure and precipitation, as well as Arctic Oscillation index and North Atlantic Oscillation index. Most of the obtained correlations, however, are not statistically significant, highlighting the need to analyse a longer time period in order to evaluate the impact of different factors on the airborne beryllium-7 activity concentration.

10.
Anal Chem ; 90(3): 2389-2394, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29318875

RESUMO

A novel plug-and-play setup based on polycapillary X-ray optics enables three-dimensional (3D) confocal X-ray fluorescence (XRF) and X-ray absorption spectroscopy down to 8 × 8 × 11 µm3 (17 keV) at the European Synchrotron Radiation Facility Collaborative Research Group Dutch-Belgian Beamline, BM26A. A complete description and analytical characterization is presented, together with two recently performed experimental cases. In Deep Earth diamond São Luiz-Frankfurt am Main 16, an olivine-rich inclusion was mapped with full 3D XRF elemental imaging. The preliminary tests on Iron Gall ink contained in an historical document, a letter from the court of King Philip II of Spain, reveal both the delicate nature of Iron Gall ink and the lack of Fe-Ni chemical bonding.

11.
World J Emerg Surg ; 9: 34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24808922

RESUMO

We describe the laparoscopic management of diaphragmatic hernia (DH) caused by vertebral pedicle screw displacement. A 58-year-old woman underwent surgery for scoliosis and underwent posterior pedicle screw fixation. In the first postoperative (PO)day, she developed mild dyspnea. An anteroposterior chest radiograph revealed bilateral pleural effusion, which was more pronounced on the left side. A thoracoabdominal computed tomography (CT) scan, performed in the second PO day, revealed a solid mass in the pleural cavity that was associated with screw displacement, which had also entered into the peritoneal cavity without apparent other lesion of hollow and solid viscous. In the third PO day, after the screw was removed, explorative laparoscopy was carried out. We observed herniation of the omentum through a small diaphragmatic tear. Once the absence of visceral injury was confirmed, we reduced the omentum into the abdomen. Then, we repaired the hernia by applying a dual layer polypropylene mesh over the defect with a 3-cm overlap. The remainder of the postoperative period was uneventful. Iatrogenic DH due to a pedicle screw displacement has never been described before. In cases of pleural effusion following spinal surgery, rapid assessment and treatment are crucial. We conclude that a laparoscopic approach to iatrogenic DH could be feasible and effective in a hemodynamically stable patient with negative CT findings because it enables the completion of the diagnostic cascade and the repair of the tear, providing excellent visualization of the abdominal viscera and diaphragmatic tears.

12.
Dalton Trans ; 43(16): 6108-19, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24522514

RESUMO

We present a thorough characterization of the interaction of novel nickel(II) (1), copper(II) (2) and zinc(II) (3) Schiff base complexes with native calf thymus DNA (ct-DNA), in buffered aqueous solution at pH 7.5. UV-vis absorption, circular dichroism (CD) and viscometry titrations provided clear evidence of the intercalative mechanism of the three square-planar metal complexes, allowing us to determine the intrinsic DNA-binding constants (K(b)), equal to 1.3 × 10(7), 2.9 × 10(6), and 6.2 × 10(5) M(-1) for 1, 2 and 3, respectively. Preferential affinity, of one order of magnitude, toward AT compared to GC base pair sequences was detected by UV-vis absorption titrations of 1 with [poly(dG-dC)]2 and [poly(dA-dT)]2. Structural details of the intercalation site of the three metal complexes within [dodeca(dA-dT)]2 were obtained by molecular dynamics (MD) simulations followed by density functional theory/molecular mechanics (DFT/MM) calculations. The calculations revealed that three major intermolecular interactions contribute to the strong affinity between DNA and the three metal complexes: (1) the electrostatic attraction between the two positively charged triethylammoniummethyl groups of the metal complexes and the negatively charged phosphate groups of the DNA backbone; (2) the intercalation of the naphthalene moiety within the four nitrogen bases of the intercalation site; (3) the metal coordination by exocyclic donor atoms of the bases, specifically the carbonyl oxygen and amine nitrogen atoms. Remarkably, the Gibbs formation free energy calculated for the intercalation complexes of 1, 2 and 3 with [dodeca(dA-dT)]2 in the implicit water solution is in agreement with the experimental Gibbs free energy values obtained from the DNA-binding constants as ΔG° = -RT ln(K(b)). In particular, the DNA-binding affinity trend, 1 > 2 > 3, is reproduced. Finally, the first shell coordination distances calculated for the intercalation complex 3/[dodeca(dA-dT)]2 are in excellent agreement with the experimental distances extracted from the extended X-ray absorption fine structure (EXAFS) spectrum of the corresponding 3/ct-DNA solutions. The latter results provided the first evidence of metal ion coordination by native DNA in aqueous solution.


Assuntos
Complexos de Coordenação/química , Cobre/química , DNA/química , Substâncias Intercalantes/química , Níquel/química , Zinco/química , Dicroísmo Circular , Simulação de Dinâmica Molecular , Bases de Schiff/química , Espectrofotometria Ultravioleta , Espectroscopia por Absorção de Raios X
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