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Upon in vivo administration of nanoparticles, a protein corona forms on their surface and affects their half-life in circulation, biodistribution properties, and stability; in turn, the composition of the protein corona depends on the physico-chemical properties of the nanoparticles. We have previously observed lipid composition-dependent in vitro and in vivo microRNA delivery from lipid nanoparticles. Here, we carried out an extensive physico-chemical characterisation to understand the role of the lipid composition on the in vivo fate of lipid-based nanoparticles. We used a combination of differential scanning calorimetry (DSC), membrane deformability measurements, isothermal titration calorimetry (ITC), and dynamic light scattering (DLS) to probe the interactions between the nanoparticle surface and bovine serum albumin (BSA) as a model protein. The lipid composition influenced membrane deformability, improved lipid intermixing, and affected the formation of lipid domains while BSA binding to the liposome surface was affected by the PEGylated lipid content and the presence of cholesterol. These findings highlight the importance of the lipid composition on the protein-liposome interaction and provide important insights for the design of lipid-based nanoparticles for drug delivery applications.
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Nanopartículas , Coroa de Proteína , Lipossomos , Distribuição Tecidual , Nanopartículas/química , Calorimetria , Soroalbumina Bovina/química , LipídeosRESUMO
The treatment of posterior eye segment diseases through intravitreal injection requires repeated injections of an active molecule, which may be associated with serious side effects and poor patient compliance. One brilliant strategy to overcome these issues is the use of drug-loaded microparticles for sustained release, aiming at reducing the frequency of injections. Therefore, the aim of this work was to assess the safety features of poly(lactic-co-glycolic acid) (PLGA)-based, hyaluronic acid-decorated microparticles loaded with palmitoylethanolamide (PEA), citicoline (CIT), or glial-cell-derived neurotrophic factor (GDNF). Microparticles were prepared by double emulsion-solvent evaporation and fully characterized for their technological features. Microparticles possessed a satisfactory safety profile in vitro on human retinal pigment epithelial (ARPE-19) cells. Interestingly, the administration of free GDNF led to a loss of cell viability, while GDNF sustained release displayed a positive effect in that regard. In vivo results confirmed the safety profile of both empty and loaded microparticles. Overall, the outcomes suggest that the produced microparticles are promising for improving the local administration of neuroprotective molecules. Further studies will be devoted to assess the therapeutic ability of microparticles.
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This study aimed to examine the impact of different surface properties of poly(lactic-co-glycolic) acid (PLGA) nanoparticles (P NPs) and PLGA-Poloxamer nanoparticles (PP NPs) on their in vivo biodistribution. For this purpose, NPs were formulated via nanoprecipitation and loaded with diphenylhexatriene (DPH), a fluorescent dye. The obtained NPs underwent comprehensive characterization, encompassing their morphology, technological attributes, DPH release rate, and thermodynamic properties. The produced NPs were then administered to wild-type mice via intraperitoneal injection, and, at scheduled time intervals, the animals were euthanized. Blood samples, as well as the liver, lungs, and kidneys, were extracted for histological examination and biodistribution analysis. The findings of this investigation revealed that the presence of poloxamers led to smaller NP sizes and induced partial crystallinity in the NPs. The biodistribution and histological results from in vivo experiments evidenced that both, P and PP NPs, exhibited comparable concentrations in the bloodstream, while P NPs could not be detected in the other organs examined. Conversely, PP NPs were primarily sequestered by the lungs and, to a lesser extent, by the kidneys. Future research endeavors will focus on investigating the behavior of drug-loaded NPs in pathological animal models.
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Nanopartículas , Poloxâmero , Camundongos , Animais , Portadores de Fármacos/química , Ácido Poliglicólico/química , Ácido Láctico/química , Distribuição Tecidual , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Nanopartículas/química , Tamanho da PartículaRESUMO
The widespread use of synthetic plastics, as well as the waste produced at the end of their life cycle, poses serious environmental issues. In this context, bio-based plastics, i.e., natural polymers produced from renewable resources, represent a promising alternative to petroleum-based materials. One potential source of biopolymers is waste from the food industry, the use of which also provides a sustainable and eco-friendly solution to waste management. Thus, the aim of this work concerns the extraction of polysaccharide fractions from lemon, tomato and fennel waste. Characterizing the chemical-physical and thermodynamic properties of these polysaccharides is an essential step in evaluating their potential applications. Hence, the solubility of the extracted polysaccharides in different solvents, including water and organic solvents, was determined since it is an important parameter that determines their properties and applications. Also, acid-base titration was carried out, along with thermoanalytical tests through differential scanning calorimetry. Finally, the electrospinning of waste polysaccharides was investigated to explore the feasibility of obtaining polysaccharide-based membranes. Indeed, electrospun fibers are a promising structure/system via which it is possible to apply waste polysaccharides in packaging or well-being applications. Thanks to processing feasibility, it is possible to electrospin waste polysaccharides by combining them with different materials to obtain porous 3D membranes made of nanosized fibers.
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Plásticos , Polissacarídeos , Biopolímeros/química , Plásticos/química , Solventes , Manipulação de AlimentosRESUMO
Self-assembling nanoparticles (SANPs) promise an effective delivery of bisphosphonates or microRNAs in the treatment of glioblastoma (GBM) and are obtained through the sequential mixing of four components immediately before use. The self-assembling approach facilitates technology transfer, but the complexity of the SANP preparation protocol raises significant concerns in the clinical setting due to the high risk of human errors during the procedure. In this work, it was hypothesized that the SANP preparation protocol could be simplified by using freeze-dried formulations. An in-depth thermodynamic study was conducted on solutions of different cryoprotectants, namely sucrose, mannitol and trehalose, to test their ability to stabilize the produced SANPs. In addition, the ability of SANPs to deliver drugs after lyophilization was assessed on selected formulations encapsulating zoledronic acid in vitro in the T98G GBM cell line and in vivo in an orthotopic mouse model. Results showed that, after lyophilization optimization, freeze-dried SANPs encapsulating zoledronic acid could retain their delivery ability, showing a significant inhibition of T98G cell growth both in vitro and in vivo. Overall, these results suggest that freeze-drying may help boost the industrial development of SANPs for the delivery of drugs to the brain.
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Glioblastoma , Nanopartículas , Animais , Difosfonatos/farmacologia , Liofilização , Glioblastoma/tratamento farmacológico , Camundongos , Sacarose , Trealose , Ácido ZoledrônicoRESUMO
Nanoparticles (NPs) coated with hyaluronic acid (HA) seem to be increasingly promising for targeted therapy due to HA chemical versatility, which allows them to bind drugs of different natures, and their affinity with the transmembrane receptor CD-44, overexpressed in tumor cells. However, an essential aspect for clinical use of NPs is formulation stability over time. For these reasons, analytical techniques capable of characterizing their physico-chemical properties are needed. In this work, poly(lactide-co-glycolide) (PLGA) NPs with an average diameter of 100-150 nm, coated with a few 10 s of nm of HA, were synthesized. For stability characterization, two complementary investigative techniques were used: Dynamic Light Scattering (DLS) and Surface-Enhanced Raman Scattering (SERS) spectroscopy. The first technique provided information on size, polidispersity index, and zeta-potential, and the second provided a deeper insight on the NP surface chemicals, allowing distinguishing of HA-coated NPs from uncoated ones. Furthermore, in order to estimate formulation stability over time, NPs were measured and monitored for two weeks. SERS results showed a progressive decrease in the signal associated with HA, which, however, is not detectable by the DLS measurements.
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Nanopartículas , Análise Espectral Raman , Ácido Hialurônico/química , Nanopartículas/química , Portadores de FármacosRESUMO
The aim of this research is to obtain new data about the complexation between ß-cyclodextrin (ß-CD) and benzoic acid (BA) as a model reaction of the complex formation of hydrophobic molecules with cyclodextrins (CDs) in various media. This research may help developing cyclodextrin-based pharmaceutical formulations through the choice of the appropriate solvent mixture that may be employed in the industrial application aiming to control the reactions/processes in liquid phase. In this paper, NMR results for the molecular complex formation between BA and ß-CD ([BAâß-CD]) in D2O-DMSO-d6 and in D2O-EtOH have shown that the stability of the complex in the H2O-DMSO-d6 varies within the experimental error, while decreases in H2O-EtOH. Changes in the Gibbs energy of BA resolvation in water and water-dimethylsulfoxide mixtures have been obtained and have been used in the analysis of the reagent solvation contributions into the Gibbs energy changes of the [BAâß-CD] molecular complex formation. Quantum chemical calculations of the interaction energy between ß-CD and BA as well as the structure of the [BAâß-CD] complex and the energy of ß-CD and BA interaction in vacuum and in the medium of water, methanol and dimethylsulfoxide solvents are carried out. The stability of [BAâß-CD] complex in H2O-EtOH and H2O-DMSO solvents, obtained by different methods, are compared. The thermodynamic parameters of the [BAâß-CD] molecular complexation as well as the reagent solvation contributions in H2O-EtOH and H2O-DMSO mixtures were analyzed by the solvation-thermodynamic approach.
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This work describes the development of liposomes encapsulating curcumin (CURC) aiming to provide insights on the influence of CURC on the thermodynamic and skin permeation/penetration features of the vesicles. CURC-loaded liposomes were prepared by hydration of lipid film, in the 0.1-15% CURC:DPPC w/w ratio range. The obtained formulations were characterized for their size distribution, zeta potential and vesicle deformability, along with their thermodynamic properties and ex vivo skin penetration/permeation ability. Liposome size was 110-130 nm for all formulations, with fairly narrow size distribution (polydispersity index was ≤0.20) and a zeta potential mildly decreasing with CURC loading. DSC outcomes indicated that CURC interferes with the packing of DPPC acyl chains in liposome bilayer when CURC percentage was at least 10%, leading to a more fluid state than blank and low-payload vesicles. Consistently, the deformability index of liposomes with 15% CURC:DPPC was strongly increased compared to other formulations. This is congruent with ex vivo skin penetration/permeation results, which showed how more deformable liposomes showed an improved deposition in the epidermis, which acts as a reservoir for the active molecule. Altogether, results hint at a possible application of high payload liposomes for improved topical dermal accumulations of actives.
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1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Curcumina/química , Curcumina/farmacocinética , Lipossomos/química , Pele , 1,2-Dipalmitoilfosfatidilcolina/química , Animais , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Humanos , Teste de Materiais , Suínos , TermodinâmicaRESUMO
Combination chemotherapy by means of two or more drugs is prone to suppressing or discouraging the inception of multidrug resistance, exploiting the fact that diverse drugs act in different points of the cellular cycle of amplifying tumor cells. For example, the combination of gemcitabine (GMC) with quercetin (QCT) showed a synergistic effect in inhibiting the migration of pancreatic cancer cells. Consequently, herein GMC and QCT have been loaded within biodegradable nanoparticles (NPs) based on poly(lactic-co-glycolic acid), externally decorated with hyaluronic acid (HA; viz., PPHA NPs), which plays a major role in drug targeting to tumors due to its ability to specifically interact with CD44 receptor, that is overexpressed in many tumors. The produced HA-decorated NPs loaded with GMC and QCT showed an improved cytotoxicity and cellular uptake toward two cell lines of pancreatic ductal adenocarcinoma, namely Mia-PaCa-2 and PANC-1, compared with both the bare drugs and the drugs loaded in NPs which do not expose HA on the surface. HA-decorated NPs were also able to improve the anti-inflammatory properties of QCT, therefore leading to a decrease of interleukin cellular levels in both cell lines, preliminarily stimulated with lipopolysaccharides. This result is of special interest also considering the crucial role of interleukins in progression, metastatic processes, and drug resistance of human pancreas cancer cells.
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Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Portadores de Fármacos/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Quercetina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/farmacologia , Sinergismo Farmacológico , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Nanopartículas/administração & dosagem , GencitabinaRESUMO
PURPOSE: Vitamin K1 (VK1) is a molecule abundant in some species of leaf vegetables with beneficial effects in humans following administration on the skin. This work investigates the possibility to use formulations based on lipid vesicles, namely liposomes, transfersomes and ethosomes, suitable to be administered on the skin by nebulization and alternative to fat semisolid preparations present on the market. METHODS: Lipid vesicles encapsulating VK1 were prepared and characterized. Ex-vivo experiments on Franz cells were carried out to study the VK1 accumulation/permeation in/through the skin. Vesicles interaction with the skin was investigated by confocal laser scanning microscopy (CLSM) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. RESULTS: All developed carriers were stable following long-term storage and were not altered following nebulization. In ex-vivo experiments, vesicles with the highest deformability index, namely transfersomes and ethosomes, led to an enhanced VK1 accumulation/permeation into/through the skin. Interestingly, the nebulization of the vesicles led to a further increase of VK1 accumulation into the skin. CONCLUSIONS: In conclusion, to achieve a local effect of VK1 on the skin, the topical nebulization of VK1-containing transfersomes could offer a good compromise between a high VK1 penetration into the skin and a limited permeation through it.
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Lipossomos/química , Absorção Cutânea , Pele/metabolismo , Vitamina K 1/administração & dosagem , Vitaminas/administração & dosagem , Administração Cutânea , Animais , Lipídeos/química , SuínosRESUMO
Radiocapitellar prosthetic arthroplasty is a fascinating new option in the treatment of complex lesions of the elbow. The device has been developed in order to treat primitive and post-traumatic radiocapitellar degenerative arthritis, while preserving the ulnohumeral joint of the elbow. Compared to a radial head resection, it avoids valgus and axial instability of the elbow and forearm preventing ulnohumeral degeneration. Seven patients have been reviewed with a mean of follow-up of 40 months. Two of them presented with an acute trauma and five of them with a post-traumatic degenerative arthritis involving the radial compartment of the elbow. The patients' evaluation was performed using DASH and Mayo elbow performance score (MEPS). Implant overstuffing, loosening and degenerative changes of the ulnohumeral joint have been monitored with X-ray controls. All patients presented with a marked improvement in elbow function, no signs of overstuffing or ulnohumeral degeneration were observed. Two patients developed a clinically asymptomatic aseptic loosening of the radial press-fit stem. The radiocapitellar prosthetic arthroplasty shows convincing results in the treatment of symptomatic radiocapitellar degenerative arthritis. It has also been effective in acute trauma scenarios in the presence of major osteoarticular wearing or loss of the entire radiocapitellar joint.
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Artroplastia , Lesões no Cotovelo , Articulação do Cotovelo , Prótese de Cotovelo/efeitos adversos , Instabilidade Articular , Osteoartrite , Complicações Pós-Operatórias , Adulto , Artroplastia/efeitos adversos , Artroplastia/instrumentação , Artroplastia/métodos , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/fisiopatologia , Articulação do Cotovelo/cirurgia , Feminino , Humanos , Itália , Instabilidade Articular/diagnóstico , Instabilidade Articular/etiologia , Instabilidade Articular/fisiopatologia , Instabilidade Articular/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico , Osteoartrite/etiologia , Osteoartrite/cirurgia , Avaliação de Processos e Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/diagnóstico , Amplitude de Movimento Articular , Estudos RetrospectivosRESUMO
We tested the common assumption that fleshy fruits become dependent on phloem water supply because xylem inflow declines at the onset of ripening. Using two distinct grape genotypes exposed to drought stress, we found that a sink-driven rise in phloem inflow at the beginning of ripening was sufficient to reverse drought-induced berry shrinkage. Rewatering accelerated berry growth and sugar accumulation concurrently with leaf photosynthetic recovery. Interrupting phloem flow through the peduncle prevented the increase in berry growth after rewatering, but interrupting xylem flow did not. Nevertheless, xylem flow in ripening berries, but not berry size, remained responsive to root or shoot pressurization. A mass balance analysis on ripening berries sampled in the field suggested that phloem water inflow may exceed growth and transpiration water demands. Collecting apoplastic sap from ripening berries showed that osmotic pressure increased at distinct rates in berry vacuoles and apoplast. Our results indicate that the decrease in xylem inflow at the onset of ripening may be a consequence of the sink-driven increase in phloem inflow. We propose a conceptual model in which surplus phloem water bypasses the fruit cells and partly evaporates from the berry surface and partly moves apoplastically to the xylem for outflow.
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Metabolismo dos Carboidratos/fisiologia , Frutas/fisiologia , Floema/fisiologia , Vitis/fisiologia , Água/metabolismo , Xilema/fisiologia , Carboidratos/fisiologia , Desidratação/metabolismo , Frutas/metabolismo , Pressão Osmótica/fisiologia , Floema/metabolismo , Raízes de Plantas/fisiologia , Brotos de Planta/fisiologia , Vitis/metabolismo , Água/fisiologia , Xilema/metabolismoRESUMO
A major issue in chemotherapy is the lack of specificity of many antitumor drugs, which cause severe side effects and an impaired therapeutic response. Here we report on the design and characterization of model tumor activated prodrug-conjugated polystyrene (PS) nanoparticles (TAP-NPs) for the release of doxorubicin (Dox) triggered by matrix metalloprotease-2 (MMP2) enzyme, which is overexpressed in the extracellular matrix of tumors. In particular, TAP-NPs were produced by attaching Dox to poly(ethylene glycol) (PEG) through two MMP2-cleavable enzymes. The resulting adduct was then tethered to PS NPs. Results showed that Dox release was actually triggered by MMP2 cleavage and was dependent on enzyme concentration, with a plateau around 20 nM. Furthermore, significant cell cytotoxicity was observed towards three cell lines only in the presence of MMP2, but not in cells without enzyme pre-treatment, even after NP internalization by cells. These findings indicate the potential of TAP-NPs as suitable nanocarriers for an on demand, tumor--specific delivery of antitumor drugs after the response to an endogenous stimulus. Further advancements will focus on the translation of this production technology to biodegradable systems for the safe transport of cytotoxic drug to tumor tissues.
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Antineoplásicos/farmacocinética , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Nanopartículas/química , Pró-Fármacos/farmacocinética , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/toxicidade , Portadores de Fármacos/toxicidade , Células Endoteliais da Veia Umbilical Humana , Humanos , Metaloproteinase 2 da Matriz , Nanopartículas/toxicidade , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/toxicidadeRESUMO
BACKGROUND: Hinged external fixation of the elbow is an important tool for the orthopedic surgeon. It enables early postoperative mobilization that may result in better outcomes. All models require correct alignment with the elbow axis of rotation. There is a long learning curve to this procedure, it may be time-consuming, and it can be associated with a high dose of x-ray exposure. An axial pin can interfere with bone-ligament suture anchors and bone reconstruction plates. MATERIALS AND METHODS: A new external fixator has been designed and mechanically tested. The hinge has a special gear able to freely align itself with the center of elbow rotation during passive flexion-extension movements. It has been clinically tested on 7 patients affected by traumatic and post-traumatic elbow disorders. The maintenance of the correct position has been tested clinically with computed tomography scans and radiographs. RESULTS: All patients had correct alignment of the axis of rotation of the external fixator with the axis of elbow rotation. No cases of misalignment, loss of fixation, pin loosening, or instability were found. CONCLUSION: A new self-centering hinged external fixator correctly aligns itself with the axis of elbow rotation. It does not interfere with ligamentous reconstruction anchors, distal plates, or screw fixation. The surgical technique is easy to learn and relatively quick. It can also be positioned without performing an arthrotomy to maintain reduction of simple dislocations of the elbow.
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Articulação do Cotovelo/cirurgia , Fixadores Externos , Instabilidade Articular/cirurgia , Adulto , Idoso , Desenho de Equipamento , Feminino , Humanos , Luxações Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Lesões no CotoveloRESUMO
Polymer chain entanglements in organic solvents can be considered a key parameter in the formation of non-spherical beads when electrospraying is employed. The shape of micro/nanometric drug delivery systems plays a major role since it can affect circulation, extravasation, distribution and in vivo clearance of the devices. In this frame, we investigated the influence of polymer processing parameters on the design of polylactic-co-glycolic acid non-spherical microdevices loaded with triamcinolone acetonide (TrA), a sparingly water soluble corticosteroid, prepared by electrospraying technique through a one-step process. In particular, we verified that the formation of non-spherical MDs is related to the presence of entanglements among polymer chains to select the optimal solution to be sprayed. The addition of TrA did not substantially affect the particle morphology in terms of size, size distribution and circularity at all the tested drug loadings. Furthermore, the drug could be released for a prolonged period, with controlled and reproducible kinetics for over 3 weeks. The mathematical modeling of release profiles highlighted that the release is mainly driven by degradation, at a higher extent in the case of low drug loading.
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Sistemas de Liberação de Medicamentos , Desenho de Equipamento , Ácido Láctico/química , Ácido Poliglicólico/química , Microscopia Eletrônica de Varredura , Copolímero de Ácido Poliláctico e Ácido PoliglicólicoRESUMO
Chronic wounds are marked by an extended healing period during which damaged tissues fail to undergo orderly and timely repair. Examples of chronic wounds encompass venous ulcers, pressure ulcers, and diabetic foot ulcers. The process of wound healing is complex and dynamic, relying on the interplay and response among various cells and mediators. In this study, four marketed wound dressing products based on cotton gauzes impregnated with different semisolid products (namely Betadine® 10%, Connettivina® Bio Plus Fitostimoline® Plus, and Non-Ad® gauzes) have been characterized for their physicochemical properties and ex vivo behaviors. More in detail, the pH and rheological features of semisolid formulations impregnating the gauzes were analyzed along with their ability to adhere to the gauzes. The most promising ones were selected and compared in ex vivo experiments on fresh pig skin. The pH measurements showed an acidic environment for all the tested solutions, albeit with variations in mean values, ranging from 2.66 to 4.50. The outcomes of rheological studies demonstrated that all the semisolid preparations impregnating the gauzes exhibited a pseudoplastic behavior, with significant differences in the pseudoplasticity index across the preparations, which is likely to influence their ability to adhere to the gauze. A rheological study in oscillatory mode revealed rheological behavior typical of a viscous solution only for the cream impregnating non-paraffin gauzes. The other products exhibited rheological behavior typical of a weak gel, which is expected to be advantageous as regards the capability of the semisolid preparation to create and maintain the space within the wound and to provide protection to the injured tissue. Results of ex vivo experiments demonstrated that Fitostimoline® Plus was more effective than Connettivina® Bio Plus in promoting both skin hydration and energy.
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This study endeavored to overcome the physiological barriers hindering optimal bioavailability in ophthalmic therapeutics by devising drug delivery platforms that allow therapeutically effective drug concentrations in ocular tissues for prolonged times. Thermosensitive drug delivery platforms were formulated by blending poloxamers (F68 and F127) with low-molecular-weight hyaluronic acid (HA) in various concentrations and loaded with hydrocortisone (HC). Among the formulations examined, only three were deemed suitable based on their desirable gelling properties at a temperature close to the eye's surface conditions while also ensuring minimal gelation time for swift ocular application. Rheological analyses unveiled the ability of the formulations to develop gels at suitable temperatures, elucidating the gel-like characteristics around the physiological temperature essential for sustained drug release. The differential scanning calorimetry findings elucidated intricate hydrogel-water interactions, indicating that HA affects the water-polymer interactions within the gel by increasing the platform hydrophilicity. Also, in vitro drug release studies demonstrated significant hydrocortisone release within 8 h, governed by an anomalous transport mechanism, prompting further investigation for optimized release kinetics. The produced platforms offer promising prospects for efficacious ocular drug delivery, addressing pivotal challenges in ocular therapeutics and heralding future advancements in the domain.
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A big challenge in tumor targeting by nanoparticles (NPs), taking advantage of the enhanced permeability and retention effect, is the fabrication of small size devices for enhanced tumor penetration, which is considered fundamental to improve chemotherapy efficacy. The purposes of this study are (i) to engineer the formulation of doxorubicin-loaded poly(D,L-lactic-co-glycolic acid) (PLGA)-block-poly(ethylene glycol) (PEG) NPs to obtain <100 nm devices and (ii) to translate standard 2D cytotoxicity studies to 3D collagen systems in which an initial step gradient of the NPs is present. Doxorubicin release can be prolonged for days to weeks depending on the NP formulation and the pH of the release medium. Sub-100 nm NPs are effectively internalized by HeLa cells in 2D and are less cytotoxic than free doxorubicin. In 3D, <100 nm NPs are significantly more toxic than larger ones towards HeLa cells, and the cell death rate is affected by the contributions of drug release and device transport through collagen. Thus, the reduction of NP size is a fundamental feature from both a technological and a biological point of view and must be properly engineered to optimize the tumor response to the NPs.
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Implantes Absorvíveis , Preparações de Ação Retardada/administração & dosagem , Doxorrubicina/administração & dosagem , Nanocápsulas/administração & dosagem , Neoplasias Experimentais/tratamento farmacológico , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/química , Difusão , Doxorrubicina/química , Células HeLa , Humanos , Teste de Materiais , Nanocápsulas/química , Neoplasias Experimentais/patologia , Resultado do TratamentoRESUMO
Drug-eluting beads (DEBs) are embolising devices in clinical use for the treatment of liver cancer by transarterial chemoembolisation. In this study, release kinetics of doxorubicin (DOX) and irinotecan (IRI) were investigated by experimental evaluations and mathematical modeling, based on Langmuir isotherm and two phenomenological models (Boyd/Bhaskar) developed to determine the actual mechanisms controlling drug release rate. The model was validated through release studies, in particular by assessing how drug loading, ionic strength of the release medium and device swelling during release influence drug release kinetics. Results demonstrated that IRI is released much faster than DOX, and that DEB volume strongly depends upon drug loading and fractional release. This effect was properly taken into account in developing the mathematical model. Experimental results were well fit by numerical simulations, and two different rate-controlling mechanisms were found to govern DOX and IRI delivery.
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Camptotecina/análogos & derivados , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Antineoplásicos/administração & dosagem , Camptotecina/administração & dosagem , Difusão , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Hidrogéis/química , Irinotecano , Cinética , Neoplasias Hepáticas/tratamento farmacológico , Modelos Teóricos , Tamanho da Partícula , Fatores de Tempo , Água/químicaRESUMO
Osteoarthritis of the hip is a common pathology and involves forms of disability and need for treatments that affect the quality of life of patients and their families, and in general of the whole society. It should be considered as such degenerative joint disease is increasing as the increase in life expectancy and musculoskeletal trauma, the latter responsible for secondary forms of osteoarthritis. The treatment of osteoarthritis of the hip has changed a lot over the years, since the earlier diagnosis and, before, with prevention through proper lifestyle. More in-depth knowledge of the biology of the tissues involved, first of all hyaline cartilage, has lead to non-surgical treatments such as infiltration with hyaluronic acid (viscosupplementation) and autologous growth factors derived from platelets (platelet rich plasma). Surgical therapy with prosthetic replacement is finally a choice to share with the patient based on pain and functional limitation, bearing in mind always the best technology and tribology and the possibility of less invasive surgical access, while recognizing that there are not still eternal prosthesis. Of particular importance then is the age of the patient. There are also other types of surgery (hip arthroscopy, forage) for other pathologies of the hip which can be resolutive, or, in a sense, can delay the arrival to the prosthetic replacement. We will discuss below the decision-making process that leads the surgeon with the patient to the surgery option.