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1.
Biomedicines ; 12(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38672133

RESUMO

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.

2.
Gels ; 10(3)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38534611

RESUMO

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.

3.
J Liposome Res ; 34(1): 88-96, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37337884

RESUMO

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.


Assuntos
Nanopartículas , Coroa de Proteína , Lipossomos , Distribuição Tecidual , Nanopartículas/química , Calorimetria , Soroalbumina Bovina/química , Lipídeos
4.
Int J Mol Sci ; 24(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37833971

RESUMO

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.


Assuntos
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 Partícula
5.
Molecules ; 28(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37836737

RESUMO

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.


Assuntos
Plásticos , Polissacarídeos , Biopolímeros/química , Plásticos/química , Solventes , Manipulação de Alimentos
6.
Pharmaceutics ; 15(8)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37631292

RESUMO

Chronic skin exposure to external hostile agents (e.g., UV radiation, microorganisms, and oxidizing chemicals) may increase oxidative stress, causing skin damage and aging. Because of their well-known skincare and protective benefits, quercetin (Q) and omega-3 fatty acids (ω3) have attracted the attention of the dermocosmetic and pharmaceutical sectors. However, both bioactives have inherent properties that limit their efficient skin delivery. Therefore, nanostructured lipid carriers (NLCs) and enriched PFC® hydrogels (HGs) have been developed as a dual-approach vehicle for Q and/or ω3 skin topical administration to improve bioactives' stability and skin permeation. Two NLC formulations were prepared with the same lipid composition but differing in surfactant composition (NLC1-soy lecithin and poloxamer 407; NLC2-Tween® 80 and dioctyl sodium sulfosuccinate (DOSS)), which have an impact on physicochemical properties and pharmaceutical and therapeutic performance. Despite both NLCs presenting high Q loading capacity, NLC2's physicochemical properties make them more suitable for topical skin administration and ensure longer colloidal stability. Additionally, NLC2 demonstrated a more sustained Q release, indicating higher bioactive storage while improving permeability. The occlusive effect of NLCs-enriched HGs also has a positive impact on skin permeability. Q-loaded NLC2, with or without ω3, -enriched HGs demonstrated efficacy as antioxidant and photoprotective formulations as well as effective reduction in S. aureus growth, indicating that they constitute a promising approach for topical skin administration to prevent skin aging and other damaging cutaneous processes.

7.
Biomacromolecules ; 24(8): 3510-3521, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37531486

RESUMO

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.

8.
Int J Pharm ; 636: 122798, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36889417

RESUMO

Chemical and enzymatic in vivo degradation of antimicrobial peptides represents a major challenge for their therapeutic use to treat bacterial infections. In this work, anionic polysaccharides were investigated for their ability to increase the chemical stability and achieve sustained release of such peptides. The investigated formulations comprised a combination of antimicrobial peptides (vancomycin (VAN) and daptomycin (DAP)) and anionic polysaccharides (xanthan gum (XA), hyaluronic acid (HA), propylene glycol alginate (PGA) and alginic acid (ALG)). VAN dissolved in buffer of pH 7.4 and incubated at 37 °C showed first order degradation kinetics with a reaction rate constant kobs of 5.5 × 10-2 day-1 corresponding with a half-life of 13.9 days. However, once VAN was present in a XA, HA or PGA-based hydrogel, kobs decreased to (2.1-2.3) × 10-2 day-1 while kobs was not affected in an alginate hydrogel and a dextran solution (5.4 × 10-2 and 4.4 × 10-2 day-1). Under the same conditions, XA and PGA also effectively decreased kobs for DAP (5.6 × 10-2 day-1), whereas ALG had no effect and HA even increased the degradation rate. These results demonstrate that the investigated polysaccharides (except ALG for both peptides and HA for DAP) slowed down the degradation of VAN and DAP. DSC analysis was used to investigate on polysaccharide ability to bind water molecules. Rheological analysis highlighted that the polysaccharides containing VAN displayed an increase in G' of their formulations, pointing that the peptides interaction act as crosslinker of the polymer chains. The obtained results suggest that the mechanism of stabilization of VAN and DAP against hydrolytic degradation is conferred by electrostatic interactions between the ionizable amine groups of the drugs and the anionic carboxylate groups of the polysaccharides. This, in turn, results in a close proximity of the drugs to the polysaccharide chain, where the water molecules have a lower mobility and, therefore, a lower thermodynamic activity.


Assuntos
Peptídeos Antimicrobianos , Daptomicina , Preparações de Ação Retardada , Vancomicina , Polissacarídeos , Hidrogéis/química
9.
Int J Mol Sci ; 23(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35563529

RESUMO

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.


Assuntos
Glioblastoma , Nanopartículas , Animais , Difosfonatos/farmacologia , Liofilização , Glioblastoma/tratamento farmacológico , Camundongos , Sacarose , Trealose , Ácido Zoledrônico
10.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614044

RESUMO

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.


Assuntos
Nanopartículas , Análise Espectral Raman , Ácido Hialurônico/química , Nanopartículas/química , Portadores de Fármacos
11.
Eur J Trauma Emerg Surg ; 48(6): 4577-4584, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34041552

RESUMO

PURPOSE: Volar rim fractures of the distal radius are a spectrum of pathology that must be well identified and treated to achieve good outcomes and avoid surgical failures. New devices of fragment specific fixation have been developed during the last decades to fix this fragment. The purpose of this retrospective study was to evaluate the ability of APTUS® wrist distal radius system to securely fix different types of volar rim fractures. METHODS: Patients with at least 1 year of follow-up and a preoperative CT-scan evaluation of the fracture pattern were included in the study. Clinical, radiological and functional outcomes were assessed. RESULTS: Sixty-eight patients with an average follow-up of 34, 1 months (12-61) were included in the study. There were no clinical and radiological complications, including loss of reduction, device failure and tendon ruptures. No patients required hardware removal. Wrist range of motion in flexion-extension averaged 96°, while in pronation-supination 144°. At final follow-up mean visual analogue scale pain was 1,8. Questionnaires, as dissabilities of the arm, shouldder and hand (DASH) score and patient-related wrist evolution (PRWE) score were 6,6 and 3 respectively. Grip strenght measured 86% compared to the normal side. CONCLUSION: APTUS® wrist presents a versatile set of fragment specific fixation plates able to easily and securely fix all types of volar rim fracture. The system can be used with other devices without any kind of interference between them. When correctly placed and used with the right indications, no late complications can be recorded.


Assuntos
Fraturas do Rádio , Humanos , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Rádio (Anatomia) , Fixação Interna de Fraturas , Estudos Retrospectivos , Punho , Placas Ósseas , Amplitude de Movimento Articular , Resultado do Tratamento
12.
Drug Deliv Transl Res ; 12(8): 1811-1828, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34755281

RESUMO

The skin is the absorption site for drug substances intended to treat loco-regional diseases, although its barrier properties limit the permeation of drug molecules. The growing knowledge of the skin structure and its physiology have supported the design of innovative nanosystems (e.g. liposomal systems) to improve the absorption of poorly skin-permeable drugs. However, despite the dozens of clinical trials started, few topically applied liposomal systems have been authorized both in the EU and the USA. Indeed, the intrinsic complexity of the topically applied liposomal systems, the higher production costs, the lack of standardized methods and the more stringent guidelines for assessing their benefit/risk balance can be seen as causes of such inefficient translation. The present work aimed to provide an overview of the physicochemical and biopharmaceutical characterization methods that can be applied to topical liposomal systems intended to be marketed as medicinal products, and the current regulatory provisions. The discussion highlights how such methodologies can be relevant for defining the critical quality attributes of the final product, and they can be usefully applied based on the phase of the life cycle of a liposomal product: to guide the formulation studies in the early stages of development, to rationally design preclinical and clinical trials, to support the pharmaceutical quality control system and to sustain post-marketing variations. The provided information can help define harmonized quality standards able to overcome the case-by-case approach currently applied by regulatory agencies in assessing the benefit/risk of the topically applied liposomal systems.


Assuntos
Lipossomos , Absorção Cutânea , Lipossomos/química , Pele/metabolismo
13.
Colloids Surf B Biointerfaces ; 210: 112240, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34864635

RESUMO

Here we aimed to correlate different molecular weights of hyaluronic acid (HA), 200, 800 and 1437 kDa, used to decorate poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs), to their cell uptakes. NP internalization kinetics in CD44-overexpressing breast carcinoma cells were quantified, using healthy fibroblast cells as reference. Actually, NP uptake and selectivity by tumor cells were maximized for NPs HA 800 kDa, while being minimum for NPs HA1400 kDa. This unexpected result could be explained considering that the interaction between NPs and tumor cells is dictated by rearrangement and conformation of that segment of HA chain that actually protrudes from the NPs. Overall, results obtained in this work point at how HA molecular weight, is pivotal project parameter in NP formulation to promote active targeting in the CD44 overexpressing cancer cells.


Assuntos
Ácido Hialurônico , Nanopartículas , Linhagem Celular Tumoral , Receptores de Hialuronatos , Peso Molecular , Polissacarídeos
14.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361559

RESUMO

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 ([BA⊂ß-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 [BA⊂ß-CD] molecular complex formation. Quantum chemical calculations of the interaction energy between ß-CD and BA as well as the structure of the [BA⊂ß-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 [BA⊂ß-CD] complex in H2O-EtOH and H2O-DMSO solvents, obtained by different methods, are compared. The thermodynamic parameters of the [BA⊂ß-CD] molecular complexation as well as the reagent solvation contributions in H2O-EtOH and H2O-DMSO mixtures were analyzed by the solvation-thermodynamic approach.

15.
J Hand Surg Eur Vol ; 46(8): 818-824, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34139911

RESUMO

We report the outcomes of delayed primary repair of flexor tendons in Zone 2 in 31 fingers and thumb (28 patients) averaging 15 days (range 4-37) after injury in 2020. The delay was longer than usual due to the COVID-19 pandemic. The tendons were repaired with a 6-strand core suture (M-Tang method) or a double Tsuge suture and a peripheral suture. This was followed by an early, partial-range, active flexion exercise programme. Adhesions in four digits required tenolysis. These patients were not with longest delay. Outcomes of two improved after tenolysis. The other two patients declined further surgery. One finger flexor tendon ruptured in early active motion. This was re-repaired, and final outcome was good. Overall excellent and good results using the Tang criteria were in 27 out of 31 fingers and thumbs (87%). The time elapsed between the injury and surgery is not an important risk factor for a good outcome, rather it depends on proper surgical methods, the surgeon's experience and early mobilization, properly applied. Adhesions may occur, but they can be managed with tenolysis.Level of evidence: IV.


Assuntos
COVID-19 , Traumatismos dos Dedos , Traumatismos dos Tendões , Traumatismos dos Dedos/cirurgia , Humanos , Pandemias , Amplitude de Movimento Articular , SARS-CoV-2 , Técnicas de Sutura , Traumatismos dos Tendões/cirurgia , Tendões/cirurgia
16.
Polymers (Basel) ; 12(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911693

RESUMO

In this study, poly(lactic-co-glycolic acid) microspheres (PLGA MS)for controlled protein release by double emulsion-solvent evaporation were produced and characterized for their morphological and technological features. MS autocatalytic degradation was described by a mathematical model based on a Michaelis and Menten-like chemical balance. Here, for the first time MS degradation was correlated to the advancement of MS degradation front with respect to the degraded radius, derived from mass loss experiments. The model can satisfactorily describe the kinetics of advancement of the degradation front experimentally derived for all MS formulations, especially when produced at higher PLGA concentrations.

17.
J Mech Behav Biomed Mater ; 110: 103885, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32957192

RESUMO

The biomedical applications of physically entangled polymeric hydrogels are generally limited due to their weak mechanical properties, rapid swelling and dissolution in physiologically relevant environment. Chemical crosslinking helps stabilizing hydrogel structure and enhancing mechanical properties, thereby allowing a higher stability in phisiological environment. In this context, it is known that the mechanical properties of the hydrogel are affected by both the molecular weight (MW) of the starting polymer and the concentration of the crosslinker. Here, our aim was to assess the influence of polymer MW and concentration in the precursor solution on the mechanical features of the final hydrogel and their influence on cells-material interaction. In detail, 3D synthetic matrices based on poly(ethylene glycol) diacrylate (PEGDA) at two molecular weights (PEG 700 and PEG 3400) and at three different concentrations (10, 20, 40 w/v %), which were photopolymerized using darocour as an initiator, were studied. Then, infrared and swelling analyses, along with a comprehensive mechanical characterization of the obtained hydrogels (i.e. oscillatory shear and confined compression tests), were performed. Finally, to evaluate the influence of the mechanical features on the biological behaviour, the hydrogels were characterized in terms of cell adhesion percentage and cell viability after functionalizing the substrates with RGD peptide at three different concentrations. Results have demonstrated that both the Young's modulus (E) in compression and the elastic modulus (G') in shear of the hydrogels increase with increasing polymer precursor concentration. E decreased as MW increased, and the differences are more relevant for more concentrated hydrogels. On the contrary, G' appears to increase with increasing PEGDA MW and in particular for the lowest polymer precursor concentration. The biological results have demonstrated that cells cultured for longer times seem to prefer PEG 3400 hydrogels with a larger mesh size structure that posses higher viscoelastic properties in shear.


Assuntos
Polietilenoglicóis , Engenharia Tecidual , Materiais Biocompatíveis , Hidrogéis , Peso Molecular
18.
J Hand Surg Eur Vol ; 45(7): 700-708, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32493112

RESUMO

Dorsal dislocations and fracture-dislocations of the radiocarpal joint are a spectrum of pathology involving both the bony and ligamentous structures that stabilize the radiocarpal joint. We retrospectively reviewed 63 dorsal radiocarpal dislocations treated in our Institute in order to propose a new classification and define surgical treatment. Preoperative CT-scan findings together with clinical and radiological outcomes were recorded. We identified four main types of lesions: Type I, pure dorsal radiocarpal dislocation; Type IIA, dorsal wall impaction and radial styloid avulsion; Type IIB, as IIA with additional intra-articular die punch; Type III, volar and dorsal marginal fragments; Type IV, larger volar and dorsal fragments. For each type of lesion, we propose specific options for treatment that are progressively more invasive. We believe that this classification adequately addresses the whole spectrum of bony and soft tissue injuries that occurs in dorsal radiocarpal fracture-dislocations giving a practical guide for surgical treatment.Level of evidence: IV.


Assuntos
Fratura-Luxação , Luxações Articulares , Fraturas do Rádio , Traumatismos do Punho , Fratura-Luxação/diagnóstico por imagem , Fratura-Luxação/cirurgia , Humanos , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Estudos Retrospectivos , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/cirurgia , Articulação do Punho
19.
Spinal Cord Ser Cases ; 6(1): 31, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355201

RESUMO

INTRODUCTION: In individuals with tetraplegia, elbow extension is critical for overhead activities, weight shifting, independent transfers, and to perform self-care tasks such as eating. At present, restoration of elbow extension in tetraplegic patients can be performed using either tendon or nerve transfers. Each procedure presents several advantages and limitations that must be discussed with the potential surgical candidate, based on remaining muscular functions and functional goals. CASE PRESENTATION: We propose a novel combined technique of both tendon and nerve transfer to restore active elbow extension by transferring the posterior deltoid tendon to the triceps tendon and the branch of teres minor nerve to the long head of the triceps nerve. Techniques were performed from the same shoulder posterior surgical approach. DISCUSSION: This surgical technique can add the benefits of each tendon and nerve transfer, leading to a reduction of failure rates, with more predictable outcomes.


Assuntos
Cotovelo/cirurgia , Transferência de Nervo/métodos , Quadriplegia/fisiopatologia , Quadriplegia/cirurgia , Transferência Tendinosa/métodos , Adulto , Articulação do Cotovelo/inervação , Articulação do Cotovelo/cirurgia , Humanos , Masculino , Resultado do Tratamento , Adulto Jovem
20.
J Mater Sci Mater Med ; 31(2): 18, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965329

RESUMO

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.


Assuntos
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 , Termodinâmica
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