Pancreatoblastoma in a paediatric patient: anatomo-pathological aspects of a case with multiple hepatic metastases

Pancreatoblastoma is a rare paediatric malignant neoplasm. The treatment of choice is complete surgical resection. However, it is often unresectable due to its large size, local infiltration or distant metastasis. Since the condition is rare, there is currently no standard treatment regimen. We outline the case of a 4-year-old child who presented with abdominal pain and distention, together with an enlarged liver and elevated serum α-fetoprotein levels. Imaging studies showed the presence of an abnormal pancreatic tumour and multiple nodular lesions in the liver, the biopsies from which led to a diagnosis of pancreatoblastoma. In this case, the patient received cycles of neoadjuvant chemotherapy, combining cisplatin and doxorubicin. The patient subsequently underwent scheduled surgery in which the primary pancreatic lesion was resected, obtaining a circumscribed and nodular specimen measuring 7 × 6 cm and weighing 150 g. Given the extent of the metastasis, the child is currently awaiting a liver transplant.Fil: Cao, Gabriel Fernando. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mendez, Julián. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Navacchia, Daniel. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); Argentin

Multiscale Musculoskeletal Modeling of the Lower Limb to Perform Personalized Simulations of Movement

Computational modeling has been used for many decades to inform design and decision-making in several fields of engineering, such as aerospace, automotive, petroleum, and others. However, it still struggles to have a similar impact in fields of medicine, such as orthopaedics. Three of the challenges that have limited the use of computational modeling in the clinical practice and in product development are model validation, personalization, and realism. Validation is a challenge because several internal parameters of the human body, such as muscle forces, are not safely measurable in vivo and, consequently, a thorough comparison between model outputs and experimental measurements is not always possible. Personalization is an additional issue because the inherent variability across a population needs to be accounted for in a model. Finally, the computational burden of simulations performed with a musculoskeletal model limits its level of realism. The purpose of the work presented in this dissertation is to investigate the applicability of state-of-the-art tools, and propose novel approaches to foster an evolution of computational modeling in orthopaedics. Specifically, (1) the reliability of the knee contact force predictions of a musculoskeletal model commonly used in the literature was analyzed using a global probabilistic analysis for three subjects with instrumented implants; (2) subject-specific and activity-specific moment arms of the muscles spanning the knee were estimated replacing the generic passive cadaveric motion implemented in the knee joint of a musculoskeletal model with in vivo kinematics measured from stereo-radiography images; (3) subject-specific joint mechanics for 6 total knee arthroplasty patients performing daily activities was estimated with a sequential multiscale modeling approach that combined joint loads estimated with a whole body musculoskeletal model, personalized joint geometries, and subject-specific fluoroscopy-measured kinematics; finally, (4) a closed-loop muscle control strategy was designed to track experimental joint kinematics and concurrently estimate muscle forces and knee mechanics with a finite element musculoskeletal model of the lower limb including a deformable representation of the joint. The utility of the modeling techniques proposed in this dissertation is presented within a clinical perspective in order to encourage the utilization of musculoskeletal modeling for clinical applications and product development

Graphene oxide–polysulfone filters for tap water purification, obtained by fast microwave oven treatment

The availability of clean, pure water is a major challenge for the future of our society. 2-Dimensional nanosheets of GO seem promising as nanoporous adsorbent or filters for water purification; however, their processing in macroscopic filters is challenging, and their cost\ua0vs.\ua0standard polymer filters is too high. Here, we describe a novel approach to combine graphene oxide (GO) sheets with commercial polysulfone (PSU) membranes for improved removal of organic contaminants from water. The adsorption physics of contaminants on the PSU-GO composite follows Langmuir and Brunauer–Emmett–Teller (BET) models, with partial swelling and intercalation of molecules in between the GO layers. Such a mechanism, well-known in layered clays, has not been reported previously for graphene or GO. Our approach requires minimal amounts of GO, deposited directly on the surface of the polymer, followed by stabilization using microwaves or heat. The purification efficiency of the PSU-GO composites is significantly improved\ua0vs.\ua0benchmark commercial PSU, as demonstrated by the removal of two model contaminants, rhodamine B and ofloxacin. The excellent stability of the composite is confirmed by extensive (100 hours) filtration tests in commercial water cartridges

Multifunctional graphene oxide/biopolymer composite aerogels for microcontaminants removal from drinking water

Due to water depletion and increasing level of pollution from standard and emerging contaminants, the development of more efficient purification materials and technology for drinking water treatment is a crucial challenge to be addressed in the near future. Graphene oxide (GO) has been pointed as one of the most promising materials to build structure and devices for new adsorbents and filtration systems. Here, we analyzed two types of GO doped 3D chitosan-gelatin aerogels with GO sheets embedded in the bulk or deposited on the surface. Through combined structural characterization and adsorption tests on selected proxies of drinking water micropollutants, we compared both GO-embedded and GO-coated materials and established the best architecture for achieving enhanced removal efficiency toward con- taminants in water. To evaluate the best configuration, we studied the adsorption capacity of both systems on two organic molecules (i.e., fluoroquinolonic antibiotics ofloxacin and ciprofloxacin) and a heavy metal (lead Pb2\ufe) of great environmental relevance and with already proved high affinity for GO. The Pb monolayer maximum adsorption capacity qmax was 11.1 mg/g for embedded GO aerogels and 1.5 mg/g in coated GO-ones. Only minor differences were found for organic contaminants between coating and embedding approaches with an adsorption capacity of 5e8 mg/g and no adsorption was found for chitosan-gelatin control aerogels without GO. Finally, potential antimicrobial effects were found particularly for the GO-coated aerogels materials, thus corroborating the multifunctionality of the newly developed porous structures

Amino acid-driven adsorption of emerging contaminants in water by modified graphene oxide nanosheets

Graphene oxide nanosheets have shown promising adsorption properties toward emerging organic contaminants in drinking water. Here, we report a family of graphene oxide nanosheets covalently modified with amino acids and the study on their adsorption properties toward a mixture of selected contaminants, including pharmaceuticals, additives, and dyes. Graphene oxides modified with l-glutamic acid and l-methionine (GO-Glu and GO-Met) were synthesized and purified with a scalable and fast synthetic and purification procedure, and their structure was studied by combined X-ray photoelectron spectroscopy and elemental analysis. An amino acid loading of about 5% and a slight reduction (from 27% down to 14-20% oxygen) were found and associated with the adsorption selectivity. They were compared to unmodified GO, reduced GO (rGO), GO-lysine, and to the reference sample GO-NaOH. Each type of modified GO possesses a higher adsorption capacity toward bisphenol A (BPA), benzophenone-4 (BP4), and carbamazepine (CBZ) than standard GO and rGO, and the adsorption occurred within the first hour of contact time. The maximum adsorption capacity (estimated from the adsorption isotherms) was strictly related to the amino acid loading. Accordingly, molecular dynamics simulations highlighted higher interaction energies for the modified GOs than unmodified GO, as a result of higher van der Waals and hydrophobic interactions between the contaminants and the amino acid side chains on the nanosheet surface

Chemical Tailoring of β-Cyclodextrin-Graphene Oxide for Enhanced Per- and Polyfluoroalkyl Substances (PFAS) Adsorption from Drinking Water

We report on the synthesis of β-cyclodextrin (βCD) modified graphene oxide (GO) nanosheets, having different sized alkyl linkers (GO-Cn-βCD) and their exploitation as sorbent of per- and polyfluoroalkyl substances (PFAS) from drinking water. βCD were functionalized with a pending amino group, and the resulting precursors grafted to GO nanosheets by epoxide ring opening reaction. Loading of βCD units in the range 12 %–36 % was estimated by combined XPS and elemental analysis. Adsorption tests on perfluorobutanoic acid (PFBA), a particularly persistent PFAS selected as case study, revealed a strong influence of the alkyl linker length on the adsorption efficiency, with the hexyl linker derivative GO-C6-βCD outperforming both pristine GO and granular activated carbon (GAC), the standard sorbent benchmark. Molecular dynamic simulations ascribed this evidence to the favorable orientation of the βCD unit on the surface of GO which enables a strong contaminant molecules retention

Facile high-yield synthesis and purification of lysine-modified graphene oxide for enhanced drinking water purification

Lysine-covalently modified graphene oxide (GO-Lys) was prepared by an innovative procedure. Lysine brushes promote enhanced adsorption of bisphenol A, benzophenone-4 and carbamazepine contaminants from tap water, with a removal capacity beyond the state of the art

Graphene oxide doped polysulfone membrane adsorbers for the removal of organic contaminants from water

This work explored polysulfone (PS) – graphene oxide (GO) based porous membranes (PS-GO) as adsorber of seven selected organic contaminants of emerging concern (EOCs) including pharmaceuticals, personal care products, a dye and a surfactant from water. PS-GO was prepared by phase inversion method starting from a PS and GO mixture (5% w/w of GO). The porous PS-GO membranes showed asymmetric and highly porous micrometer sized pores on membrane top (diameter ≈20 μm) and bottom (diameter ≈2–5 μm) surfaces and tens of microns length finger like pores in the section. Nanomechanical mapping reveals patches of a stiffer material with Young modules comprised in the range 15–25 GPa, not present in PS pure membranes that are compatible with the presence of GO flakes on the membrane surfaces. PS-GO was immersed in EOCs spiked tap water and the adsorbance efficiency at different contact times and pH evaluated by HPLC analysis. Ofloxacin (OFLOX), benzophenone-3 (BP-3), rhodamine b (Rh), diclofenac (DCF) and triton X-100 (TRX) were removed with efficiency higher than 90% after 4 h treatments. Regeneration of PS-GO and reuse possibilities were demonstrated by washing with ethanol. The adsorption efficiencies toward OFLOX, Rh, DCF and carbamazepine (CBZ) were significantly higher than those of pure PS membrane. Moreover, PS-GO outperformed a commercial granular activated carbon (GAC) at low contact times and compared well at longer contact time for OFLOX, Rh, BP-3 and TRX suggesting the suitability of the newly introduced material for drinking water treatment

Graphene oxide-polysulfone hollow fibers membranes with synergic ultrafiltration and adsorption for enhanced drinking water treatment

Polysulfone-graphene oxide hollow fiber membranes (PSU-GO HFs) with simultaneous adsorption and ultrafiltration capabilities are herein described and proposed for enhanced and simplified Point-of-Use (POU) drinking water purification. The PSU-GO HFs were prepared by phase inversion extrusion by a customized semi-industrial plant and their morphology, surface properties, and porosity were investigated by combined Scanning Electron Microscopy (SEM), contact angle and Raman confocal microscopy, in relation to different GO:PSU ratios (1–5% w/w GO vs PSU) and to the final adsorption-ultrafiltration properties. Filtration modules of PSU-GO HFs of filtering surface (FS) in the range 0,015–0,28 m2 showed same ultrafiltration capability of PSU-HF standard filters. Synergic adsorption properties were demonstrated by studying the adsorption maximum capacity of ciprofloxacin antibiotic (CIPRO) vs GO ratio in dead end in-out configuration, the standard configuration used for PSU HFs commercial modules. Loading of 3,5% GO vs PSU was selected as case study, representing the best compromise between performance and GO nanofiller amount. Heavy metals (Pb, Cu and Cr(III)) and polyfluoroalkyl substances (PFAS) removal capabilities from tap water were competitive and in some cases outperformed Granular Activated Carbon (GAC), the standard industrial sorbent. Ciprofloxacin removal from tap water was also under real operational conditions. Moreover, release of GO from working PSU-GO modules was excluded by Surface Enhanced Raman Spectroscopy (SERS) analysis of treated water having the state-of-the-art limit of quantification of 0.1 μg/L for GO nanosheets