Burn wounds are highly debilitating injuries, with significant morbidity and mortality rates worldwide. In association with the damage of the skin integrity, the risk of infection is increased, ...posing an obstacle to healing and potentially leading to sepsis. Another limitation against healing is associated with antibiotic resistance mainly due to the use of systemic antibiotics for the treatment of localized infections. Nanotechnology has been successful in finding strategies to incorporate antibiotics in nanoparticles for the treatment of local wounds, thereby avoiding the systemic exposure to the drug. This review focuses on the most recent advances on the use of nanoparticles in wound dressing formulations and in tissue engineering for the treatment of burn wound infections.
Despite the health benefits of the sun, overexposure to solar radiation without proper precautions can cause irreversible damage to exposed skin. In the search for balance between the risks and ...benefits of exposure to solar radiation in human health, a technological alternative was found, the incorporation of photoprotective products in lipid nanoparticulate systems for topical application. These nanometric systems have demonstrated several advantages when used as adjuvants in photoprotection compared to chemical and/or physical sunscreens alone. The increase in the sun protection factor (SPF), photostability and UV action spectrum are parameters that have benefited from the application of these systems in order to increase the effectiveness and safety of photoprotective formulations containing organic and/or inorganic sunscreens.
The aim of this work is development of a nontoxic, long-term stable solid lipid nanoparticles (SLN) formulation for the loading of Nimesulide (NiM) by a 2
2
factorial design. The optimized ...formulation was composed of 10 wt% of glyceryl behenate and 2.5 wt% of poloxamer 188. Immediately after production, Z-Ave of NiM-SLN was 166.1 ± 0.114 nm, with a polydispersity index (PI) of 0.171 ± 0051 and zeta potential nearly neutral (−3.10 ± 0.166 mV). A slight increase of Z-Ave was recorded for NiM-SLN stored at 25 °C for a period of 15 days, whereas at 4 °C particles kept size within similar range. Long-term stability was monitored using TurbiscanLab
®
, showing a high stability of the nanoparticles with variations in the backscattering profiles below 10%. The release profile of NiM-SLN followed a sustained pattern with ca. 30% of drug released up to 24 h. Empty-SLN and NiM-SLN were nontoxic after exposing Caco-2 cells to the highest concentration (100 μg/mL) up to 48 hours (cell viability higher than 80%). NiM-SLN were lyophilized using different cryoprotectants, producing particles of 463.1 ± 36.63 nm (PI 0.491 ± 0.027) with 5% trehalose. Solid character of NiM-SLN was confirmed by DSC, recording a recrystallization index of 83% for NiM-SLN and of 74% for lyophilized SLN.
Cutaneous leishmaniasis (CL) and mucocutaneous leishmaniasis (ML) show clinical spectra that can range from a localized lesion (with a spontaneous healing process) to cases that progress to a ...generalized systemic disease with a risk of death. The treatment of leishmaniasis is complex since most of the available drugs show high toxicity. The development of an effective topical drug formulation for CL and ML treatment offers advantages as it will improve patient’s compliance to the therapy given the possibility for self-administration, as well as overcoming the first pass metabolism and the high costs of currently available alternatives. The most common dosage forms include solid formulations, such as membranes and semi-solid formulations (e.g., ointments, creams, gels, and pastes). Topical treatment has been used as a new route of administration for conventional drugs against leishmaniasis and its combinations, as well as to exploit new substances. In this review, we discuss the advantages and limitations of using topical drug delivery for the treatment of these two forms of leishmaniasis and the relevance of combining this approach with other pharmaceutical dosage forms. Emphasis will also be given to the use of nanomaterials for site-specific delivery.
Objectives
Liposomes have attracted the attention of researchers due to their potential to act as drug delivery systems for cancer treatment. The present investigation aimed to develop liposomes ...loaded with prednisolone base and the evaluation of the antiproliferative effect on human colon carcinoma cell lines.
Methods
Liposomes were elaborated by following a reproducible thin film hydration technique. The physicochemical characterization of liposomes included photon correlation spectroscopy, microscopy analysis, Fourier transform infrared spectroscopy, rheological behaviour and electrophoresis. On the basis of these data and drug loading values, the best formulation was selected. Stability and drug release properties were also tested.
Key findings
Resulting liposomes exhibited optimal physicochemical and stability properties, an excellent haemocompatibility and direct antiproliferative effect on human colon carcinoma T‐84 cell lines.
Conclusions
This study shows direct antitumour effect of prednisolone liposomal formulation, which opens the door for liposomal glucocorticoids as novel antitumour agents.
Abstract Background Melatonin has attracted attention because of their high antioxidant and anticarcinogenic activity. Otherwise, the use of sunscreens is recommended for patients after chemotherapy ...and radiotherapy treatments or to prevent UV radiation-induced skin damages that may result in pre-cancerous and cancerous skin lesions. Objective To evaluate the beneficial influence of melatonin in topical sunscreen emulsions combined with three common ultraviolet filters. Methods After the formulation characterization in terms of rheology, stability studies were performed. Release studies let us to evaluate its mechanism of delivery and ex vivo permeation study through human skin, the amount of melatonin retained. The antioxidant activity assay was also carried out, and finally the in vivo photoprotective effect in rats was tested as transepidermal water loss and erythema formation. Results The rheological behaviour of formulations was pseudoplastic fluid, all emulsions had good physical stability. Release studies showed a trend of enhancement in melatonin release from emulsions incorporating UV filters and followed a Weibull model. Melatonin permeation was higher from the emulsion containing melatonin combined with a mixture of three ultraviolet filters (MMIX) formulation. Equally this formulation exhibited the highest radical scavenging activity. Finally the photoprotective assay showed that only skin areas treated with this formulation were statistically equivalent to the unirradiated control area. Conclusion MMIX formulation would be a promising formulation for preventing the undesirable adverse effects of UV skin irradiation because melatonin not only acts as a potent antioxidant itself, but also is capable of activating an endogenous enzymatic protective system against oxidative stress.
A new paromomycin micellar nanogel based on poloxamer 407 was developed.
In vitro release and ex vivo permeation/retention studies were conducted. In vivo tolerance was assayed by transepidermal ...water loss. Ex vivo cytotoxicity on RAW and VERO cells and antileishmanial activity on Leishmania promastigotes was tested.
The particle size was 9.19 nm (99% loading efficiency) exhibiting Newtonian behavior at 4°C and was pseudoplastic at 25 and 40°C. Drug release followed a Weibull model and the drug remaining in the skin was 31.652 µg/g/cm(2). In vivo tolerance achieved excellent results with negligible cellular toxicity and the best antileishmanial efficiency.
The nanogel provided controlled, effective and safe delivery of paromomycin for the treatment of cutaneous leishmaniasis.
Critical limb ischemia (CLI) is associated with significant morbidity and mortality. In this study, we developed and characterized an intra-arterial cell suspension containing human mesenchymal stem ...cells (hMSCs) for the treatment of CLI. Equally, the stability of cells was studied in order to evaluate the optimal conditions of storage that guarantee the viability from cell processing to the administration phase. Effects of various factors, including excipients, storage temperature and time were evaluated to analyze the survival of hMSCs in the finished medicinal product. The viability of hMSCs in different packaging media was studied for 60h at 4°C. The best medium to maintain hMSCs viability was then selected to test storage conditions (4, 8, 25 and 37°C; 60h). The results showed that at 4°C the viability was maintained above 80% for 48h, at 8°C decreased slightly, whereas at room temperature and 37°C decreased drastically. Its biocompatibility was assessed by cell morphology and cell viability assays. During stability study, the stored cells did not show any change in their phenotypic or genotypic characteristics and physicochemical properties remained constant, the ability to differentiate into adipocytes and osteocytes and sterility requirements were also unaltered. Finally, our paper proposes a packing media composed of albumin 20%, glucose 5% and Ringer’s lactate at a concentration of 1×106cells/mL, which must be stored at 4°C as the most suitable to maintain cell viability (>80%) and without altering their characteristics for more than 48h.
The main goal of this study was the design, development and characterization of a poloxamer/chitosan/hyaluronic based vehicle including three biological antioxidant molecules such as vitamins A, D ...and E aimed at improving the treatment of skin burns. The physical characterization of hydrogel, its mechanical and rheological properties as well as internal structure were investigated. Furthermore, biological characteristics such as ex vivo antimicrobial properties and in vivo wound healing were also accomplished and compared with a commercial reference. Results showed optimal physicochemical properties with biocompatible pH value of 4.6 ± 0.1 and zeta potential dependent on pH. The swelling rate was around 350% with optimal wettability, adhesion and leakage properties, as well as thermosensitive gelation processes. The microbiological assay demonstrated similar antimicrobial activity to that of commercial reference. In vivo tolerance study revealed no skin reactions. Finally, the wound healing efficacy of hydrogel in skin burn model showed dermal appendages and similar epidermis, dermis and stratum corneum to the commercial reference. These findings indicated that our hydrogel loading vitamins could be considered an outstanding candidate for further clinical studies.
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