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1.
Pharmaceuticals (Basel) ; 15(10)2022 Sep 24.
Article in English | MEDLINE | ID: mdl-36297297

ABSTRACT

Transmucosal delivery is commonly used to prevent or treat local diseases. Pranoprofen is an anti-inflammatory drug prescribed in postoperative cataract surgery, intraocular lens implantation, chorioretinopathy, uveitis, age-related macular degeneration or cystoid macular edema. Pranoprofen can also be used for acute and chronic management of osteoarthritis and rheumatoid arthritis. Quality by Design (QbD) provides a systematic approach to drug development and maps the influence of the formulation components. The aim of this work was to develop and optimize a nanostructured lipid carrier by means of the QbD and factorial design suitable for the topical management of inflammatory processes on mucosal tissues. To this end, the nanoparticles loading pranoprofen were prepared by a high-pressure homogenization technique with Tween 80 as stabilizer and Lanette® 18 as the solid lipid. From, the factorial design results, the PF-NLCs-N6 formulation showed the most suitable characteristics, which was selected for further studies. The permeability capacity of pranoprofen loaded in the lipid-based nanoparticles was evaluated by ex vivo transmucosal permeation tests, including buccal, sublingual, nasal, vaginal, corneal and scleral mucosae. The results revealed high permeation and retention of pranoprofen in all the tissues tested. According to the predicted plasma concentration at the steady-state, no systemic effects would be expected, any neither were any signs of ocular irritancy observed from the optimized formulation when tested by the HET-CAM technique. Hence, the optimized formulation (PF-NLCs-N6) may offer a safe and attractive nanotechnological tool in topical treatment of local inflammation on mucosal diseases.

2.
Pharmaceutics ; 11(8)2019 Jul 24.
Article in English | MEDLINE | ID: mdl-31344882

ABSTRACT

Oleanolic (OA) and ursolic (UA) acids are recognized triterpenoids with anti-cancer properties, showing cell-specific activity that can be enhanced when loaded into polymeric nanoparticles. The cytotoxic activity of OA and UA was assessed by Alamar Blue assay in three different cell lines, i.e., HepG2 (Human hepatoma cell line), Caco-2 (Human epithelial colorectal adenocarcinoma cell line) and Y-79 (Human retinoblastoma cell line). The natural and synthetic mixtures of these compounds were tested as free and loaded in polymeric nanoparticles in a concentration range from 2 to 32 µmol/L. The highest tested concentrations of the free triterpene mixtures produced statistically significant cell viability reduction in HepG2 and Caco-2 cells, compared to the control (untreated cells). When loaded in the developed PLGA nanoparticles, no differences were recorded for the tested concentrations in the same cell lines. However, in the Y-79 cell line, a decrease on cell viability was observed when testing the lowest concentration of both free triterpene mixtures, and after their loading into PLGA nanoparticles.

3.
Nanomaterials (Basel) ; 8(12)2018 Dec 07.
Article in English | MEDLINE | ID: mdl-30544628

ABSTRACT

Pranoprofen (PF)-loaded nanostructured lipid carriers (NLCs), prepared using a high-pressure homogenization method, have been optimized and characterized to improve the biopharmaceutical profile of the drug. The optimized PF-NLCs exhibited physicochemical characteristics and morphological properties that were suitable for dermal application. Stability assays revealed good physical stability, and the release behavior of PF from these NLCs showed a sustained release pattern. Cell viability results revealed no toxicity. Ex vivo human skin permeation studies in Franz diffusion cells were performed to determine the influence of different skin penetration enhancers (pyrrolidone, decanol, octanoic acid, nonane, menthone, squalene, linoleic acid, and cineol) on skin penetration and retention of PF, being the highest dermal retention in the presence of linoleic acid. The selected formulations of NLCs exhibited a high retained amount of PF in the skin and no systemic effects. In vivo mice anti-inflammatory efficacy studies showed a significant reduction in dermal oedema. NLCs containing linoleic acid presented better anti-inflammatory efficacy by decreasing the production of interleukins in keratinocytes and monocytes. The biomechanical properties of skin revealed an occlusive effect and no hydration power. No signs of skin irritancy in vivo were detected. According to these results, dermal PF-NLCs could be an effective system for the delivery and controlled release of PF, improving its dermal retention, with reduced dermal oedema as a possible effect of this drug.

4.
Nanomedicine (Lond) ; 13(19): 2397-2413, 2018 10.
Article in English | MEDLINE | ID: mdl-30311846

ABSTRACT

AIM: The design and development of pranoprofen (PF) nanostructured lipid carriers (NLCs) for topical treatment of local inflammation and pain. MATERIALS & METHODS: PF-NLCs were designed and optimized by central rotatable composite design. A physicochemical characterization was addressed. Release and skin permeation were performed in Franz diffusion cells. In vivo anti-inflammatory efficacy was assayed in mice and tolerance study in humans. RESULTS: PF-NLCs F7 and F10 provided sustained release, good stability and optimal skin retention avoiding systemic undesired side effects. Anti-inflammatory activity was enhanced, suggesting an improved efficacy as compared with standard formulation. No skin irritancy was detected. CONCLUSION: Topical PF-NLCs F7 and F10 could be effective and safe new therapeutic tools for the treatment of local inflammation and pain. [Formula: see text].


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Benzopyrans/administration & dosage , Inflammation/drug therapy , Nanoparticles/administration & dosage , Propionates/administration & dosage , Administration, Topical , Animals , Benzopyrans/chemistry , Delayed-Action Preparations , Drug Carriers/chemistry , Humans , Inflammation/pathology , Lipids/administration & dosage , Lipids/chemistry , Mice , Nanoparticles/chemistry , Nanostructures/chemistry , Propionates/chemistry , Skin/drug effects , Skin Absorption/drug effects
5.
Int J Pharm ; 511(2): 719-27, 2016 Sep 25.
Article in English | MEDLINE | ID: mdl-27480398

ABSTRACT

Pranoprofen (PF) is a NSAID considered as a safe anti-inflammatory treatment for strabismus and/or cataract surgery. The drug has been formulated in poly (lactic/glycolic) acid (PLGA) nanoparticles (PF-F1NPs with cPF 1.5mg/mL, PF-F2NPs with cPF 1mg/mL) produced by solvent displacement technique and tested the in vitro cytotoxicity, ex vivo corneal permeation, in vivo ocular tolerance and in vivo anti-inflammatory efficacy of PF-F1NPs, PF-F2NPs, in comparison to eye drops conventional dosage form (Oftalar(®), PF 1mg/mL) and free drug solution (PF dissolved in PBS, 1.5mg/mL). The mean particle size of both formulations was around 350nm, with polydispersity index below 0.1, and a net negative charge of -7.41mV and -8.5mV for PF-F1NPs and PF-F2NPs, respectively. Y-79 human retinoblastoma cell line was used to evaluate the cytotoxicity of PF-F1NPs and PF-F2NPs, which were compared to blank NPs and free drug solution (PF dissolved in PBS, 1.5mg/mL). Concentrations up to 75µg/mL exhibited no toxicity to Y-79 cells, whereas at 150µg/mL a decrease of about 80% on the cell viability was observed after exposing the cells to PF-F1NPs. When treating the Y-79 cells with concentrations of PF-F2NPs between 1µg/mL to 100µg/mL, the cell viability was similar to control values after 24h and 48h of exposure. An ex vivo corneal permeation study was carried out in New Zealand rabbits. A very similar profile has been observed for the permeation of PF through the cornea when administered as eye drops and as free drug solution, which was kept much lower in comparison to PF-NPs formulations. The permeated amount of PF from the PF-F1NPs was slightly smaller than from PF-F2NPs, attributed to the increase of viscosity of the formulations with the increase of cPVA concentration. New Zealand white rabbits were also used to evaluate the irritancy of PF-F1NPs and PF-F2NPs, which demonstrated to be well-tolerated to the eye (i.e. the mean total score (MTS) was 0). PF-F2NPs exhibited the highest QP (amounts of PF permeated in the cornea) and significantly reduced the ocular edema compared to the tested formulations. The QR (amounts of PF retained in the cornea) of the PF-F1NPs was greater than that obtained for PF-F2NPs.


Subject(s)
Benzopyrans/pharmacology , Benzopyrans/pharmacokinetics , Lactic Acid/chemistry , Nanoparticles/chemistry , Polyglycolic Acid/chemistry , Propionates/pharmacology , Propionates/pharmacokinetics , Administration, Ophthalmic , Animals , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Benzopyrans/adverse effects , Benzopyrans/chemistry , Cell Survival/drug effects , Cells, Cultured , Cornea/metabolism , Dose-Response Relationship, Drug , Edema/prevention & control , Humans , Nanoparticles/ultrastructure , Ophthalmic Solutions/adverse effects , Ophthalmic Solutions/chemistry , Ophthalmic Solutions/pharmacokinetics , Ophthalmic Solutions/pharmacology , Particle Size , Polylactic Acid-Polyglycolic Acid Copolymer , Propionates/adverse effects , Propionates/chemistry , Rabbits
6.
Int J Pharm ; 501(1-2): 350-61, 2016 Mar 30.
Article in English | MEDLINE | ID: mdl-26844786

ABSTRACT

Pranoprofen (PF)-loaded nanoparticles (PF-F1NPs and PF-F2NPs) have been formulated into blank hydrogels (HG_PF-F1NPs and HG_PF-F1NPs) or into hydrogels composed of 3% azone (HG_PF-F1NPs-Azone and HG_PF-F2NPs-Azone), as innovative strategy to improve the biopharmaceutical profile of the selected non-steroidal anti-inflammatory drug (Pranoprofen, PF) for topical application. The purpose of this approach has been to increase the contact of PF with the skin, improve its retention in deeper layers, thus enhancing its anti-inflammatory and analgesic effects. The physicochemical characterization of the developed hydrogels showed a non-Newtonian behaviour, typical of semi-solid formulations for skin administration, with sustained release profile. The results obtained from ex vivo skin human permeation and in vivo anti-inflammatory efficacy studies suggest that topical application of HG_PF-F2NPs has been more effective in the treatment of oedema on the skin' surface in comparison to other hydrogels. No signs of skin irritancy have been detected for all the semi-solid formulations containing 0% or 3% azone.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Benzopyrans/administration & dosage , Drug Carriers/administration & dosage , Hydrogels/administration & dosage , Nanoparticles/administration & dosage , Propionates/administration & dosage , Adult , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/toxicity , Benzopyrans/chemistry , Benzopyrans/therapeutic use , Benzopyrans/toxicity , Drug Carriers/chemistry , Drug Carriers/therapeutic use , Drug Carriers/toxicity , Drug Liberation , Edema/chemically induced , Edema/drug therapy , Female , Humans , Hydrogels/chemistry , Hydrogels/therapeutic use , Hydrogels/toxicity , In Vitro Techniques , Lactic Acid/chemistry , Male , Mice , Nanoparticles/chemistry , Nanoparticles/therapeutic use , Nanoparticles/toxicity , Polyglycolic Acid/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer , Propionates/chemistry , Propionates/therapeutic use , Propionates/toxicity , Rabbits , Skin/metabolism , Skin Absorption , Skin Irritancy Tests , Tetradecanoylphorbol Acetate , Viscosity
7.
Int J Pharm ; 501(1-2): 10-7, 2016 Mar 30.
Article in English | MEDLINE | ID: mdl-26826569

ABSTRACT

The purpose of this study was the development of poly(d,l-lactide-co-glycolide) acid (PLGA) nanoparticles (NPs) for the dermal delivery of carprofen (CP). The developed nanovehicle was then lyophilized using hydroxypropyl-ß-cyclodextrin (HPßCD) as cryoprotectant. The ex vivo permeation profiles were evaluated using Franz diffusion cells using three different types of skin membranes: human, porcine and bovine. Furthermore, biomechanical properties of skin (trans-epidermal water loss and skin hydration) were tested. Finally, the in vivo skin irritation and the anti-inflammatory efficacy were also assayed. Results demonstrated the achievement of NPs 187.32 nm sized with homogeneous distribution, negatively charged surface (-23.39 mV) and high CP entrapment efficiency (75.38%). Permeation studies showed similar diffusion values between human and porcine skins and higher for bovine. No signs of skin irritation were observed in rabbits. Topically applied NPs significantly decreased in vivo inflammation compared to the reference drug in a TPA-induced mouse ear edema model. Thus, it was concluded that NPs containing CP may be a useful tool for the dermal treatment of local inflammation.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Carbazoles/administration & dosage , Nanoparticles/administration & dosage , Skin/metabolism , 2-Hydroxypropyl-beta-cyclodextrin , Administration, Topical , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/therapeutic use , Anti-Inflammatory Agents/toxicity , Carbazoles/chemistry , Carbazoles/therapeutic use , Carbazoles/toxicity , Cattle , Edema/chemically induced , Edema/drug therapy , Female , Freeze Drying , Humans , In Vitro Techniques , Lactic Acid/chemistry , Male , Mice , Nanoparticles/chemistry , Nanoparticles/therapeutic use , Nanoparticles/toxicity , Polyglycolic Acid/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer , Rabbits , Skin/drug effects , Swine , Tetradecanoylphorbol Acetate , beta-Cyclodextrins/chemistry
8.
Nanomedicine ; 11(3): 521-30, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25659643

ABSTRACT

Oleanolic acid (OA) and ursolic acid (UA) are ubiquitous pentacyclic triterpenes compounds in plants with great interest as anti-inflammatory therapeutics. The aim of this study was the design and optimization of polymeric nanoparticles (NPs) loaded with natural and synthetic mixtures (NM, SM) of these drugs for ophthalmic administration. A 2(3) + star central rotatable composite design was employed to perform the experiments. Results showed optimal and stable formulations with suitable physicochemical properties (mean diameter<225 nm), homogeneous distribution (polydispersity index∼0.1), negatively charged surface (∼-27 mV) and high entrapment efficiency (∼77%). Release and corneal permeation studies showed that NM release was faster than SM. Amounts of drug retained in the corneal tissue were also higher for NM. In vitro and in vivo tests showed no signs of irritation or toxicity and successful in vivo anti-inflammatory efficacy for both formulations, being NM-OA/UA NPs the most effective. From the clinical editor: Oleanolic acid (OA) and ursolic acid (UA) are compounds found in plants with anti-inflammatory properties. The authors in this paper designed nanoparticles (NPs) using poly(dl-lactide-coglycolide) acid (PLGA) loaded with these compounds for ophthalmic administration. Both in vitro and in vivo experiments showed no toxicity and significant anti-inflammatory efficacy. This may provide new drugs for ocular anti-inflammatory treatment.


Subject(s)
Anti-Inflammatory Agents , Drug Delivery Systems/methods , Drug Design , Eye Diseases , Nanoparticles/chemistry , Oleanolic Acid , Triterpenes , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacokinetics , Anti-Inflammatory Agents/pharmacology , Drug Evaluation, Preclinical , Eye Diseases/drug therapy , Oleanolic Acid/chemistry , Oleanolic Acid/pharmacokinetics , Oleanolic Acid/pharmacology , Rabbits , Triterpenes/chemistry , Triterpenes/pharmacokinetics , Triterpenes/pharmacology , Ursolic Acid
9.
Eur J Pharm Biopharm ; 95(Pt B): 261-70, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25681744

ABSTRACT

Two optimized pranoprofen-loaded poly-l-lactic-co glycolic acid (PLGA) nanoparticles (PF-F1NPs; PF-F2NPs) have been developed and further dispersed into hydrogels for the production of semi-solid formulations intended for ocular administration. The optimized PF-NP suspensions were dispersed in freshly prepared carbomer hydrogels (HG_PF-F1NPs and HG_PF-F2NPs) or in hydrogels containing 1% azone (HG_PF-F1NPs-Azone and HG_PF-F2NPs-Azone) in order to improve the ocular biopharmaceutical profile of the selected non-steroidal anti-inflammatory drug (NSAID), by prolonging the contact of the pranoprofen with the eye, increasing the drug retention in the organ and enhancing its anti-inflammatory and analgesic efficiency. Carbomer 934 has been selected as gel-forming polymer. The hydrogel formulations with or without azone showed a non-Newtonian behavior and adequate physicochemical properties for ocular instillation. The release study of pranoprofen from the semi-solid formulations exhibited a sustained release behavior. The results obtained from ex vivo corneal permeation and in vivo anti-inflammatory efficacy studies suggest that the ocular application of the hydrogels containing azone was more effective over the azone-free formulations in the treatment of edema on the ocular surface. No signs of ocular irritancy have been detected for the produced hydrogels.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Benzopyrans/administration & dosage , Lactic Acid/chemistry , Nanoparticles , Polyglycolic Acid/chemistry , Propionates/administration & dosage , Acrylic Resins/chemistry , Administration, Ophthalmic , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Azepines/chemistry , Benzopyrans/pharmacokinetics , Benzopyrans/pharmacology , Cornea/metabolism , Delayed-Action Preparations , Drug Carriers/chemistry , Drug Liberation , Hydrogels , Male , Permeability , Polylactic Acid-Polyglycolic Acid Copolymer , Propionates/pharmacokinetics , Propionates/pharmacology , Rabbits
10.
Article in English | MEDLINE | ID: mdl-25638028

ABSTRACT

Oleanolic acid (OA) and ursolic acid (UA) are ubiquitous pentacyclic triterpenes compounds in plants. These triterpenoids exhibit unique, important biological and pharmacological activities. For the investigation and development of topical drug delivery systems of triterpenoids in Plumeria obtusa is essential an adequate detection and quantification method for its application in skin permeation studies. The aim of this study was to develop a HPLC method for the determination of OA/UA from leaves of P. obtusa. Results showed that it was sensitive, repeatable, selective, accurate and precise. The detection limit was 0.93±0.21µg/mL and the quantification limit 2.81±0.65µg/mL. Determination coefficients were higher than 0.999 for concentrations between 3.62 and 116µg/mL. The intra and inter-day precision (relative standard deviation) was less than 1.50% and accuracy in terms of relative error ranged between -1.45 and 1.39%. The proposed HPLC method presented advantageous performance characteristics and it can be considered suitable for the evaluation of OA/UA in ex vivo permeation studies.


Subject(s)
Apocynaceae/chemistry , Oleanolic Acid/analysis , Triterpenes/analysis , Chromatography, High Pressure Liquid/methods , Humans , In Vitro Techniques , Oleanolic Acid/chemistry , Permeability , Proton Magnetic Resonance Spectroscopy , Reproducibility of Results , Triterpenes/chemistry , Ursolic Acid
11.
Int J Pharm ; 473(1-2): 591-8, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25102113

ABSTRACT

The aim of this study was to develop biocompatible lipid-based nanocarriers for retinyl palmitate (RP) to improve its skin delivery, photostability and biocompatibility, and to avoid undesirable topical side effects. RP loaded nanoemulsions (NEs), liposomes (LPs) and solid lipid nanoparticles (SLNs) were characterized in terms of size, surface electrical charge, pH, drug encapsulation efficiency and morphology. Spherical-shaped nanocarriers with a negatively charged surface (>|40|mV) and mean size lower than 275 nm were produced with adequate skin compatibility. The rheological properties showed that aqueous dispersions of SLNs followed a non-Newtonian behavior, pseudoplastic fluid adjusted to Herschel-Bulkley equation, whereas LPs and NEs exhibited a Newtonian behavior. SLNs offered significantly better photoprotection than LPs and NEs for RP. The cumulative amount of drug permeated through human skin at the end of 38 h was 6.67 ± 1.58 µg, 4.36 ± 0.21 µg and 3.64 ± 0.28 µg for NEs, LPs and SLNs, respectively. NEs flux was significantly higher than SLNs and LPs: NEs (0.37 ± 0.12 µg/h) > LPs (0.15 ± 0.09 µg/h) > SLNs (0.10 ± 0.05 µg/h). LPs offered significant higher skin retention than NEs and SLNs. Finally, even though all developed nanocarriers were found to be biocompatible, according to histological studies, NE was the system that most disrupted the skin. These encouraging findings can guide in proper selection of topical carriers among the diversity of available lipid-based nanocarriers, especially when a dermatologic or cosmetic purpose is desired.


Subject(s)
Antioxidants/administration & dosage , Drug Carriers/administration & dosage , Lipids/administration & dosage , Nanoparticles/administration & dosage , Skin Absorption/drug effects , Vitamin A/analogs & derivatives , Antioxidants/chemistry , Diterpenes , Drug Carriers/chemistry , Emulsions , Humans , In Vitro Techniques , Lipids/chemistry , Liposomes , Nanoparticles/chemistry , Retinyl Esters , Rheology , Skin/metabolism , Vitamin A/administration & dosage , Vitamin A/chemistry
12.
J Pharm Sci ; 103(10): 3153-64, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25091511

ABSTRACT

Pranoprofen (PF)-loaded poly (lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) were optimized and characterized as a means of exploring novel formulations to improve the biopharmaceutical profile of this drug. These systems were prepared using the solvent displacement technique, with polyvinyl alcohol (PVA) as a stabilizer. A factorial design was applied to study the influence of several factors (the pH of the aqueous phase and the stabilizer, polymer and drug concentrations) on the physicochemical properties of the NPs. After optimization, the study was performed at two different aqueous phase pH values (4.50 and 5.50), two concentrations of PF (1.00 and 1.50 mg/mL), three of PVA (5, 10, and 25 mg/mL), and two of PLGA (9.00 and 9.50 mg/mL). These conditions produced NPs of a size appropriate particle size for ocular administration (around 350 nm) and high entrapment efficiency (80%). To improve their stability, the optimized NPs were lyophilized. X-ray, FTIR, and differential scanning calorimetry analysis confirmed the drug was dispersed inside the particles. The release profiles of PF from the primary nanosuspensions and rehydrated freeze-dried NPs were similar and exhibited a sustained drug delivery pattern. The ocular tolerance was assessed by an HET-CAM test. No signs of ocular irritancy were detected (score 0).


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Benzopyrans/administration & dosage , Freeze Drying , Lactic Acid/chemistry , Nanoparticles , Nanostructures , Polyglycolic Acid/chemistry , Propionates/administration & dosage , Chromatography, High Pressure Liquid , Ophthalmic Solutions , Polylactic Acid-Polyglycolic Acid Copolymer
13.
Rev. méd. Panamá ; 15(2): 112-8, mayo 1990. tab
Article in Spanish | LILACS | ID: lil-93286

ABSTRACT

Las infecciones nosocomiales aumentan la morbilidad, la mortalidad y el costo de la reclusión institucional. El Comité de Infecciones Nosocomiales del Complejo Hospitalario Metropolitano de la Caja de Seguro Social de Panamá (CHMCSS) hizo el estudio del problema en el año de 1987 y determinó que de un total de 29.576 pacientes admitidos, 820 pacientes desarrollaron 994 infecciones asociadas al hospital (prevalencia anual de 3.69 por ciento). Esta incidencia representó 5,191 días adicionales de reclusión, un costo conservador de $840.153 balboas, y fue la causa de 24 fallecimientos. Se recomienda un eficiente y adecuado programa de control de las infecciones asociadas al nosocomio


Subject(s)
Humans , Male , Female , Hospitals, Urban/economics , Cross Infection/economics , Panama , Social Security/economics , Hospital Departments/economics
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