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1.
Int J Pharm ; 658: 124222, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38735632

ABSTRACT

Dry eye disease (DED) is a chronic multifactorial disorder of the ocular surface caused by tear film dysfunction and constitutes one of the most common ocular conditions worldwide. However, its treatment remains unsatisfactory. While artificial tears are commonly used to moisturize the ocular surface, they do not address the underlying causes of DED. Apigenin (APG) is a natural product with anti-inflammatory properties, but its low solubility and bioavailability limit its efficacy. Therefore, a novel formulation of APG loaded into biodegradable and biocompatible nanoparticles (APG-NLC) was developed to overcome the restricted APG stability, improve its therapeutic efficacy, and prolong its retention time on the ocular surface by extending its release. APG-NLC optimization, characterization, biopharmaceutical properties and therapeutic efficacy were evaluated. The optimized APG-NLC exhibited an average particle size below 200 nm, a positive surface charge, and an encapsulation efficiency over 99 %. APG-NLC exhibited sustained release of APG, and stability studies demonstrated that the formulation retained its integrity for over 25 months. In vitro and in vivo ocular tolerance studies indicated that APG-NLC did not cause any irritation, rendering them suitable for ocular topical administration. Furthermore, APG-NLC showed non-toxicity in an epithelial corneal cell line and exhibited fast cell internalization. Therapeutic benefits were demonstrated using an in vivo model of DED, where APG-NLC effectively reversed DED by reducing ocular surface cellular damage and increasing tear volume. Anti-inflammatory assays in vivo also showcased its potential to treat and prevent ocular inflammation, particularly relevant in DED patients. Hence, APG-NLC represent a promising system for the treatment and prevention of DED and its associated inflammation.


Subject(s)
Apigenin , Drug Carriers , Dry Eye Syndromes , Lipids , Nanoparticles , Animals , Apigenin/administration & dosage , Apigenin/chemistry , Apigenin/pharmacology , Apigenin/pharmacokinetics , Drug Carriers/chemistry , Dry Eye Syndromes/drug therapy , Humans , Rabbits , Lipids/chemistry , Lipids/administration & dosage , Cell Line , Nanoparticles/chemistry , Administration, Ophthalmic , Drug Liberation , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/pharmacokinetics , Particle Size , Nanostructures/administration & dosage , Nanostructures/chemistry , Male
2.
J Comp Pathol ; 201: 37-40, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36701871

ABSTRACT

An adult male greater bulldog bat (Noctilio leporinus) was found dead in a suburban area in the municipality of Patos, Paraiba, northeastern Brazil. At post-mortem examination, the bat was emaciated and had multifocal to coalescent grey, crusted, dry, scaly cutaneous lesions, irregularly distributed over the dorsal thoracoabdominal region, muzzle, labial commissures, ears and dorsoventral surfaces of the patagia. Histopathology revealed numerous longitudinal and transverse sections of fungal organisms, with weakly basophilic walls, associated with multifocal areas of ulceration of the epidermis, necrosis, rupture and discontinuity of collagen fibres in the dermis without any inflammatory response. Molecular identification matched the organism to Cladosporium spp, Curvularia spp, Exserohilum spp, Bipolaris spp (100%) and Alternaria spp (97%), all of which have been associated with phaeohyphomycosis. Phaeohyphomycosis should be included as a differential diagnosis of cutaneous lesions in chiropterans.


Subject(s)
Chiroptera , Phaeohyphomycosis , Male , Animals , Brazil , Phaeohyphomycosis/veterinary , Skin , Cladosporium
3.
Braz J Anesthesiol ; 73(4): 373-379, 2023.
Article in English | MEDLINE | ID: mdl-34246688

ABSTRACT

INTRODUCTION: Transthoracic echocardiography is a safe and readily available tool for noninvasive monitoring of Cardiac Output (CO). The use of the suprasternal window situated at the sternal notch can be an alternative approach for estimating blood flow. The present study aimed to compare two methods of CO calculation. We compared the descending aorta Velocity-Time Integral (VTI) measurement from the suprasternal window view with the standard technique to determine CO that uses VTI measurements from the LVOT (Left Ventricular Outflow Tract) view. We also aimed to find out whether after basic training a non-echocardiographer operator can obtain reproducible measurements of VTI using this approach. METHODS: In the first part of the study, 26 patients without known cardiovascular diseases were evaluated and VTI data were acquired from the suprasternal window by a non-echocardiographer and an echocardiographer. Next, 17 patients were evaluated by an echocardiographer only and VTI and CO measurements were obtained from suprasternal and apical windows. Data were analyzed using the Bland and Altman method (BA), correlation and regression. RESULTS: We found a strong correlation between measurements obtained by a non-expert and an expert echocardiographer and detected that an inexperienced trainee can acquire VTI measurements from the suprasternal window view. Regarding agreement between CO measurements, data obtained showed a positive correlation and the Bland and Altman analysis presented a total variation of 38.9%. CONCLUSION: Regarding accuracy, it is likely that TTE (Transthoracic Echocardiogram) measurements of CO from the suprasternal window view are comparable to other minimally invasive techniques currently available. Due to its user-friendliness and low cost, it can be a convenient technique for obtaining perioperative hemodynamic measurements, even by inexperienced operators.


Subject(s)
Anesthesiologists , Echocardiography , Humans , Cardiac Output/physiology , Echocardiography/methods , Hemodynamics , Heart
4.
Braz. J. Anesth. (Impr.) ; 73(4): 373-379, 2023. tab, graf
Article in English | LILACS | ID: biblio-1447626

ABSTRACT

Abstract Introduction Transthoracic echocardiography is a safe and readily available tool for noninvasive monitoring of Cardiac Output (CO). The use of the suprasternal window situated at the sternal notch can be an alternative approach for estimating blood flow. The present study aimed to compare two methods of CO calculation. We compared the descending aorta Velocity-Time Integral (VTI) measurement from the suprasternal window view with the standard technique to determine CO that uses VTI measurements from the LVOT (Left Ventricular Outflow Tract) view. We also aimed to find out whether after basic training a non-echocardiographer operator can obtain reproducible measurements of VTI using this approach. Methods In the first part of the study, 26 patients without known cardiovascular diseases were evaluated and VTI data were acquired from the suprasternal window by a non-echocardiographer and an echocardiographer. Next, 17 patients were evaluated by an echocardiographer only and VTI and CO measurements were obtained from suprasternal and apical windows. Data were analyzed using the Bland and Altman method (BA), correlation and regression. Results We found a strong correlation between measurements obtained by a non-expert and an expert echocardiographer and detected that an inexperienced trainee can acquire VTI measurements from the suprasternal window view. Regarding agreement between CO measurements, data obtained showed a positive correlation and the Bland and Altman analysis presented a total variation of 38.9%. Conclusion Regarding accuracy, it is likely that TTE (Transthoracic Echocardiogram) measurements of CO from the suprasternal window view are comparable to other minimally invasive techniques currently available. Due to its user-friendliness and low cost, it can be a convenient technique for obtaining perioperative hemodynamic measurements, even by inexperienced operators.


Subject(s)
Humans , Echocardiography/methods , Anesthesiologists , Cardiac Output/physiology , Heart , Hemodynamics
5.
J Helminthol ; 95: e65, 2021 Nov 11.
Article in English | MEDLINE | ID: mdl-34758891

ABSTRACT

The present report describes two cases of infection by Molossinema wimsatti in the brain of Pallas's mastiff bats (Molossus molossus). The first bat was captured and killed by a domestic cat in a suburban area of the municipality of Patos, Paraiba, northeastern Brazil. The second bat was found crawling on the ground in the same area before dying. No gross lesions were found at necropsy. Histology of the central nervous system revealed filarioid nematodes in the brain ventricles and cerebellum. There were adults, subadults and eggs, the latter sometimes containing microfilariae. No inflammatory response was observed in bat 1, while bat 2 presented a mild lymphoplasmacytic meningoencephalitis. Three nematodes were recovered and submitted for parasitological examination. The diagnosis of M. wimsatti infection was based on the histomorphological and parasitological characteristics of the agent and its location in the brain ventricular system of insectivorous bats. The infection likely occurs in other insectivorous bats from South American and Caribbean countries but may be overlooked.


Subject(s)
Chiroptera , Animals , Brain/diagnostic imaging , Brazil , Cats
6.
Pharm Dev Technol ; 26(1): 92-100, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33074769

ABSTRACT

Isradipine is a dihydropyridine calcium channel blocker (CCB) commonly used as vasodilator with antihypertensive properties. A remote-controlled release formulation for isradipine would substantially improve the clinical outcomes of the patients requiring chronic long-term treatment. In this work, sustained release (SR) tablets of isradipine, composed of hydroxypropylmethyl cellulose (HPMC), have been produced by wet granulation and their in vitro and in vivo characterization was compared to a conventional tablet dosage form of immediate release (IR) as preliminary assessment. Tablets composed of 15.0% (wt/wt) HPMC exhibited a SR profile over a period of 24 hours. The release of isradipine followed a Fickian diffusion pattern obeying to the first order kinetics and the extent of absorption was even higher in comparison to the developed conventional tablets, which showed immediate drug release. In vivo studies were carried out in rabbits, showing that the extent of isradipine absorption from the developed tablets was higher in comparison to IR tablets due to the modified release profile obtained for the former (p < 0.05). Our results suggest that SR tablets of isradipine are an efficient solid dosage form to overcome the limitations encountered in conventional IR tablets.


Subject(s)
Antihypertensive Agents/chemical synthesis , Antihypertensive Agents/pharmacokinetics , Chemical Phenomena , Isradipine/chemical synthesis , Isradipine/pharmacokinetics , Animals , Antihypertensive Agents/administration & dosage , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/chemical synthesis , Delayed-Action Preparations/pharmacokinetics , Isradipine/administration & dosage , Rabbits , Tablets
7.
Int J Pharm ; 591: 120001, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33141086

ABSTRACT

The aim of this study was to develop and characterize a double layer biomembrane for dual drug delivery to be used for the treatment of wounds. The membrane was composed of chitosan, hydroxypropyl methylcellulose and lidocaine chloride (anesthetic drug) in the first layer, and of sodium alginate-polymyxin B sulphate (antibiotic) nanoparticles as the second layer. A product with excellent thickness (0.01-0.02 mm), adequate mechanical properties with respect to elasticity, stiffness, tension, and compatible pH for lesion application has been successfully obtained. The incorporation of the drugs was confirmed analysing the membrane cross-sections by scanning electron microscopy. A strong interaction between the drugs and the functional groups of respective polymers was confirmed by Fourier-Transform Infrared Spectroscopy, thermal analysis and X-ray diffraction. Microbiological assays showed a high antimicrobial activity when polymyxin B was present to act against the Staphylococcus aureus and Pseudomonas aeruginosa strains. Low cytotoxicity observed in a cell viability colorimetric assay and SEM analysis suggest biocompatibility between the developed biomembrane and the cell culture. The in vivo assay allowed visualizing the healing potential by calculating the wound retraction index and by histological analysis. Our results confirm the effectiveness of the developed innovative biomaterial for tissue repair and regeneration in an animal model.


Subject(s)
Chitosan , Nanoparticles , Alginates , Animals , Bandages , Lidocaine , Polymyxins , Spectroscopy, Fourier Transform Infrared , Wound Healing
8.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1767-1770, Sept.-Oct. 2020. ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1131570

ABSTRACT

Descrevem-se os aspectos clínicos, anatomopatológicos, imuno-histoquímicos, microbiológicos e moleculares de um caso de adenocarcinoma pulmonar associado à infecção por Mycobacterium sp. em uma vaca. O animal apresentou hiporexia, emagrecimento, vocalizações, postura ortopneica, ingurgitamento da jugular, estase venosa positiva, gemido expiratório e morte. Na necropsia, os pulmões estavam aumentados e apresentavam, na superfície pleural, nódulos branco-amarelados, firmes, multifocais a coalescentes, interpostos por áreas avermelhadas. Ao corte, os nódulos aprofundavam-se ao parênquima e possuíam múltiplos focos de aspecto caseoso e friável e áreas de mineralização. O saco pericárdico e os linfonodos traqueobrônquicos, ilíacos, lombares aórticos e mamários apresentavam lesões semelhantes. Histologicamente, observou-se neoformação carcinomatosa associada a áreas multifocais de necrose e mineralização. As células neoplásicas foram fortemente imunomarcadas pelo anticorpo antipancitoqueratina AE1/AE3. Na cultura microbiológica de fragmentos dos pulmões, houve crescimento de colônias bacterianas compatíveis com micobactérias atípicas. O sequenciamento molecular submetido ao BLASTn identificou o Mycobacterium sp. WCM 7299 (ID: gb|KJ873243.1|).(AU)


The clinical, anatomopathological, immunohistochemical, microbiological and molecular aspects of a case of pulmonary adenocarcinoma associated with infection by Mycobacterium sp. in a cow are described. The animal presented hyporexia, weight loss, vocalizations, orthopneic posture, jugular engorgement, positive venous stasis, expiratory groaning and death. At necropsy, the lungs were enlarged and presented firm, multifocal to coalescent yellowish nodules, interposed by reddish areas on the pleural surface. At cut, the nodules deepened to the parenchyma and had multiple foci of caseous and friable appearance and areas of mineralization. The pericardial sac and tracheobronchial, iliac, aortic lumbar and mammary lymph nodes showed similar lesions. Histologically, a carcinomatous neoformation, associated with multifocal areas of necrosis and mineralization, was observed. Neoplastic cells were strongly immunolabelled by anti-PanCytokeratin antibody AE1/AE3. Microbiological culture of lung fragments showed growth of bacterial colonies compatible with atypical mycobacteria. Molecular sequencing submitted to BLASTn identified the Mycobacterium sp. WCM 7299 (ID: gb|KJ873243.1|).(AU)


Subject(s)
Animals , Female , Cattle , Adenocarcinoma of Lung/veterinary , Mycobacterium/isolation & purification , Immunohistochemistry/veterinary , Lung Neoplasms/veterinary
9.
J Mycol Med ; 30(3): 101005, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32522404

ABSTRACT

The epidemiological, clinical and anatomopathological aspects of pythiosis in cats in northeastern Brazil are described. From January 2000 to December 2018 the Laboratory of Animal Pathology of the Federal University of Campina Grande received 1928 tissue samples of cats, three of which were diagnosed as pythiosis. Grossly, the cats showed a multinodular mass in the oral cavity associated with facial deformity (case 1), a large multinodular mass thickening the jejunum wall (case 2), and an ulcerated nodule in the skin at the base of the tail (case 3). Histologically, pyogranulomatous inflammation and necrosis, with intralesional predominantly negatively stained hyphae, were observed in all cases. Immunohistochemistry for Pythium insidiosum revealed strong immunolabelling of the hyphae. The diagnosis of pythiosis was based on the epidemiological, clinical and anatomopathological findings, and was confirmed by immunohistochemistry. Although uncommon in cats, pythiosis should be readily considered as a differential diagnosis of chronic pyogranulomatous infections of the gastrointestinal tract and skin, especially in endemic areas, where the disease is often diagnosed in other animal species.


Subject(s)
Cat Diseases/diagnosis , Pythiosis/diagnosis , Animals , Brazil , Cat Diseases/microbiology , Cats , Facial Asymmetry/microbiology , Facial Asymmetry/pathology , Facial Asymmetry/veterinary , Female , Inflammation/microbiology , Inflammation/pathology , Inflammation/veterinary , Male , Pythiosis/microbiology , Pythium/isolation & purification , Pythium/pathogenicity , Retrospective Studies
10.
Heliyon ; 6(5): e03831, 2020 May.
Article in English | MEDLINE | ID: mdl-32395645

ABSTRACT

Sunscreens have been employed on daily skin care for centuries. Their role in protecting the skin from sun damage, avoiding accelerated photoaging and even limiting the risk of development of skin cancer is unquestionable. Although several chemical and physical filters are approved as sunscreens for human use, their safety profile is dependent on their concentration in the formulation which governs their acceptance by the regulatory agencies. A strategic delivery of such molecules should provide a UV protection and limit the skin penetration. Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) may offer an alternative approach to achieve a synergistic effect on the UV protection when loaded with sunscreens as particles themselves also have a UV light scattering effect. Besides, the lipid character of SLN and NLC improves the encapsulation of lipophilic compounds, with enhanced loading capacity. Silica nanoparticles have also been employed in sunscreen formulations. Due to the formed sol-gel complexes, which covalently entrap sunscreen molecules, a controlled release is also achieved. In the present work, we have developed a new sunscreen formulation composed of hybrid SLN-Silica particles loaded with octyl methoxycinnamate (Parsol®MCX), and their further incorporation into a hydrogel for skin administration. Hybrid SLN-silica particles of 210.0 ± 3.341 nm of mean size, polydispersity below 0.3, zeta potential of ca. |7| mV, loading capacity of 19.9% and encapsulation efficiency of 98.3% have been produced. Despite the slight negative surface charge, the developed hybrid nanoparticles remained physicochemically stable over the study period. Turbiscan transmission profiles confirmed the colloidal stability of the formulations under stress conditions. The texture profile analysis of Parsol-SLN and Parsol-SLN-Si revealed semi-solid properties (e.g. adhesiveness, hardness, cohesiveness, springiness, gumminess, chewiness, resilience) suitable for topical application, together with the bioadhesiveness in the skin of pig ears. The non-irritation profile of the hybrid nanoparticles before and after dispersion into Carbopol hydrogels was confirmed by HET-CAM test.

11.
Pharmazie ; 75(2): 75-81, 2020 03 20.
Article in English | MEDLINE | ID: mdl-32213238

ABSTRACT

In this study we developed a mucoadhesive polymeric membrane wound dressing incorporating red propolis extract (HERP). Membranes were made using a casting method employing collagen, chitosan, polyethylene glycol (15, 20, and 30v%), and hydroethanolic extract of EtOH-H2O 70v% - 30v% (v/v) of HERP (0.5, 1.0, and 1.5%). Membranes were extensively characterized to assess the thickness, pH, morphology using Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), mechanical properties, swelling, in vitro mucoadhesion, cytotoxicity, and minimum inhibitory concentration (MIC). Assessment of the thickness and mechanical properties of the membranes containing HERP revealed that the most significant thickness obtained was 40.7 µm; thermal analysis suggests suggesting the hydrogen bonds between hydroxyl groups of isoflavones and the free amine present in the region of chitosan. Cell viability decreased as the amount of HERP increased. Finally, the MICs were 7.8 and 1.9 µg.mL-1 for Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853, respectively. These results were suggesting that the 0.5 % HERP membrane has the potential for future studies for wound application.


Subject(s)
Propolis/pharmacology , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/pharmacology , Chitosan/pharmacology , Collagen/pharmacology , Microbial Sensitivity Tests
12.
Nanomaterials (Basel) ; 10(2)2020 Feb 23.
Article in English | MEDLINE | ID: mdl-32102229

ABSTRACT

Polymer hydrogels have been suggested as dressing materials for the treatment of cutaneous wounds and tissue revitalization. In this work, we report the development of a hydrogel composed of natural polymers (sodium alginate and gelatin) and silver nanoparticles (AgNPs) with recognized antimicrobial activity for healing cutaneous lesions. For the development of the hydrogel, different ratios of sodium alginate and gelatin have been tested, while different concentrations of AgNO3 precursor (1.0, 2.0, and 4.0 mM) were assayed for the production of AgNPs. The obtained AgNPs exhibited a characteristic peak between 430-450 nm in the ultraviolet-visible (UV-Vis) spectrum suggesting a spheroidal form, which was confirmed by Transmission Electron Microscopy (TEM). Fourier Transform Infra-red (FT-IR) analysis suggested the formation of strong intermolecular interactions as hydrogen bonds and electrostatic attractions between polymers, showing bands at 2920, 2852, 1500, and 1640 cm-1. Significant bactericidal activity was observed for the hydrogel, with a Minimum Inhibitory Concentration (MIC) of 0.50 µg/mL against Pseudomonas aeruginosa and 53.0 µg/mL against Staphylococcus aureus. AgNPs were shown to be non-cytotoxic against fibroblast cells. The in vivo studies in female Wister rats confirmed the capacity of the AgNP-loaded hydrogels to reduce the wound size compared to uncoated injuries promoting histological changes in the healing tissue over the time course of wound healing, as in earlier development and maturation of granulation tissue. The developed hydrogel with AgNPs has healing potential for clinical applications.

13.
Colloids Surf B Biointerfaces ; 186: 110705, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31830707

ABSTRACT

Nowadays, a combinatorial drug delivery system that simultaneously transports two or more drugs to the targeted site in a human body, also recognized as a dual-drugs delivery system, represents a promising strategy to overcome drug resistance. Solid lipid nanoparticles loaded with clotrimazole (CLZ) and alphalipolic acid (ALA), considered as an effective agent in the reduction of reactive oxygen species, can enhance anti-infective immunity being proposed as a non-toxic and mainly non-allergic dual-drugs delivery system. In this study, uncoated and cationic CLZ-ALA-loaded SLN were prepared and compared. Suspensions with a narrow size distribution of particles of mean size below 150 nm were obtained, having slight negative or highly positive zeta potential values, due to the presence of the cationic lipid, which also increased nanoparticles stability, as confirmed by Turbiscan® results. Calorimetric studies confirmed the rationale of separately delivering the two drugs in a dual-delivery system. Furthermore, they confirmed the formation of SLN, without significant variation in presence of the cationic lipid. In vitro release studies showed a prolonged drug release without the occurrence of any burst effect. In vitro studies performed on 25 strains of Candida albicans showed the antimicrobial drug activity was not altered when it was loaded into lipid nanoparticles. The study has proved the successfully encapsulation of CLZ and ALA in solid lipid nanoparticles that may represent a promising strategy to combine ALA protective effect in the treatment with CLZ.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Clotrimazole/pharmacology , Drug Delivery Systems , Mycoses/drug therapy , Thioctic Acid/pharmacology , Antifungal Agents/chemistry , Calorimetry , Clotrimazole/chemistry , Drug Carriers/chemistry , Drug Liberation , Lipids/chemistry , Microbial Sensitivity Tests , Nanoparticles/chemistry , Particle Size , Reactive Oxygen Species/antagonists & inhibitors , Reactive Oxygen Species/metabolism , Surface Properties , Thioctic Acid/chemistry
14.
Int J Pharm ; 575: 118953, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31843548

ABSTRACT

In this study, we report the relationship between structure, self-assembly behavior and antimicrobial activity of multicationic gemini surfactants and their successful use as stabilizers of a new liposomal formulation for transdermal drug delivery. New surfactants containing natural moiety 1,4-diazabicyclo[2.2.2]octane with four charges and two hydrophobic chains (n-Dabco-s-Dabco-n, where s = 2, 6, 12 and n = 12, 14, 16, 18) were synthesized. A linear dependence of the CMC decrease, with the increase of the number of carbon atoms in alkyl groups (slope 0.23) was shown. The aggregation numbers of n-Dabco-2-Dabco-n are smaller than 30 and they decrease with increasing alkyl chain length. This is in compliance with the larger surface area per n-Dabco-2-Dabco-n molecule. New liposomal formulations loading Rhodamine B phosphatidylcholine (with mean size about 100 nm and increased zeta potential from -7 ± 2 mV to +55 ± 2 mV) have been successfully stabilized by n-Dabco-s-Dabco-n surfactants. These formulations were designed to improve the bioavailability and skin permeation of loaded compound. The antibacterial activity of Dabco-surfactants was shown to be strongly affected by their structure (alkyl chain length and number of charged nitrogen). 12-Dabco-2-Dabco-12 was the most active (MIC = 0.48, 0.98 and 15.6 µg/mL against S. aureus, B. cereus and E. coli, respectively) without hemolytic activity at 3.1 µg/mL concentration. PC/14-Dabco-2-Dabco-14-liposomes were shown to be the best formulation, with the highest antibacterial activity against Sa (MIC = 7.8 µg‧mL-1) and lowest cytotoxicity (IC50 > 125). The modification of liposomes by Dabco-surfactants stabilizes the membrane of the vesicles, preventing the release of rhodamine B and impairing the penetration of the dye across Strat-M® membrane. Cellular uptake of rhodamine B-loaded PC/12-Dabco-2-Dabco-12-liposomes was also reported. This is the first example of cationic mixed liposomes containing Dabco-surfactants of potential interest for transdermal drug delivery.


Subject(s)
Anti-Bacterial Agents/pharmacology , Liposomes/pharmacology , Piperazines/chemistry , Piperazines/pharmacology , Technology, Pharmaceutical/methods , Administration, Cutaneous , Anti-Bacterial Agents/pharmacokinetics , Aza Compounds/chemistry , Bacterial Outer Membrane Proteins , Cell Line , Cell Survival , Cyclooctanes/chemistry , Dose-Response Relationship, Drug , Fungi/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Hydrophobic and Hydrophilic Interactions , Liposomes/chemistry , Liposomes/pharmacokinetics , Micelles , Microbial Sensitivity Tests , Particle Size , Piperazines/chemical synthesis , Piperazines/pharmacokinetics , Skin/drug effects , Structure-Activity Relationship , Surface-Active Agents/chemistry , Surface-Active Agents/pharmacology
15.
Pharm Dev Technol ; 24(8): 1044-1053, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31180272

ABSTRACT

Three-dimensional (3D) printing technologies are manufacturing approaches with widespread use in industry (e.g. automotive, automobile, pharmaceutical industries). With regard to its use in pharmaceutical industry, 3D printing is demonstrating to be of added value attributed to the possibility of printing tailored pharmaceutical products, namely personalized medical devices, such as implants and other dosage forms. However, with the approval of the first 3D-printed drug-product in 2015, a new perspective has arisen, i.e. the use of this technology to produce solid oral dosage forms exhibiting complex drug release profiles and allowing for individual dosing. Technological hurdles and regulatory issues still have to be overcome before this technology can truly find its place in the healthcare sector, where it can certainly contribute to a personalized and patient-centered healthcare. This manuscript offers a comprehensive analysis of the most extensively used methods of 3D printing in the pharmaceutical field, with examples of solid oral dosage forms and other medical devices currently under development or already marketed.


Subject(s)
Pharmaceutical Preparations/chemistry , Technology, Pharmaceutical/methods , Dosage Forms , Drug Industry/methods , Drug Liberation , Printing, Three-Dimensional , Prostheses and Implants
16.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 1081-1084, May-June 2019. ilus
Article in English | VETINDEX, LILACS | ID: biblio-1038592

ABSTRACT

Uma avestruz-do-pescoço-vermelho, com dois anos de idade, apresentava um nódulo no terço médio do esôfago e foi submetida a procedimento cirúrgico. Histologicamente, observou-se uma área focalmente extensa de necrose estendendo-se da túnica mucosa à muscular, e, em algumas secções, à túnica adventícia. Circundando a área de necrose, observou-se uma reação inflamatória composta principalmente por granulócitos e macrófagos, associada à fibroplasia e neovascularização. Em meio às áreas de necrose e inflamação, verificavam-se numerosas imagens negativas de hifas em seções longitudinais e transversais, melhor apreciadas pela coloração de metenamina nitrato de prata de Grocott. O diagnóstico definitivo de infecção por Pythium insidiosum foi confirmado por imuno-histoquímica. A avestruz recebia água para consumo de um lago localizado em uma área de pastagem, no qual alguns cavalos haviam desenvolvido pitiose cutânea anteriormente.(AU)


Subject(s)
Animals , Bird Diseases , Deglutition Disorders/veterinary , Struthioniformes , Esophagitis/veterinary , Pythiosis/diagnosis
17.
Cancer Chemother Pharmacol ; 84(1): 15-32, 2019 07.
Article in English | MEDLINE | ID: mdl-31079217

ABSTRACT

Uveal melanoma is the most common primary intraocular tumor in adults. It can arise from melanocytes in the anterior (iris) or posterior uveal tract (choroid and ciliary body). Uveal melanoma has a particular molecular pathogenesis, being characterized by specific chromosome alterations and gene mutations (e.g., GNAQ/GNA11; BAP1), which are considered promising targets for molecular therapy. Primary treatment of uveal melanoma includes radiotherapy (brachytherapy and charged-particle therapy), phototherapy (photocoagulation, transpupillary thermal therapy, and photodynamic therapy) and surgery (local resection, enucleation and exenteration). Approximately half of patients with uveal melanoma will, however, develop metastasis, especially in the liver. The treatment of metastatic uveal melanoma includes systemic chemotherapy, immunotherapy and molecular targeted therapy. Liver-directed therapies, such as resection, chemoembolization, immunoembolization, radioembolization, isolated hepatic perfusion and percutaneous hepatic perfusion, are also available to treat metastatic uveal melanoma. Several clinical trials are being developed to study new therapeutic options to treat uveal melanoma, mainly for those with identified liver metastases. The present work discusses the physiopathology and new in situ-specific therapies for the treatment of uveal melanoma.


Subject(s)
Liver Neoplasms/therapy , Melanoma/pathology , Uveal Neoplasms/pathology , Adult , Chromosome Aberrations , GTP-Binding Protein alpha Subunits/genetics , GTP-Binding Protein alpha Subunits, Gq-G11/genetics , Humans , Liver Neoplasms/secondary , Melanoma/genetics , Melanoma/therapy , Mutation , Tumor Suppressor Proteins/genetics , Ubiquitin Thiolesterase/genetics , Uveal Neoplasms/genetics , Uveal Neoplasms/therapy
18.
Adv Colloid Interface Sci ; 260: 85-94, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30177215

ABSTRACT

Polyphenols are secondary metabolites found in all vascular plants and constitute a large group of at least 10,000 unique compounds. Particular attention is currently being paid to polyphenols attributed to their beneficial effects in the protection and prevention of several diseases. While their use in food, pharmaceutical and cosmetic industries is largely documented, several environmental conditions (e.g. light, temperature or oxygen) may affect the physicochemical stability of polyphenols, compromising their bioactivity in vivo. To overcome these limitations, the loading of polyphenols into nanoparticles has been proposed aiming at both increasing their bioavailability and reducing eventual side effects. Lipid nanoparticles offer several advantages, namely their biodegradability and low toxicity, with the additional capacity to modify the release profile of loaded drugs. This paper is a review of the recent advances of lipid nanocarriers commonly used for the encapsulation of polyphenols, highlighting their added value to increase bioavailability and bioactivity of this group of compounds as well as their application in several diseases.


Subject(s)
Drug Carriers/chemistry , Lipids/chemistry , Nanoparticles/chemistry , Polyphenols/chemistry , Animals , Emulsions/chemistry , Humans
19.
Int J Pharm ; 548(1): 217-226, 2018 Sep 05.
Article in English | MEDLINE | ID: mdl-29966744

ABSTRACT

Essential oils are recognized as valuable active pharmaceutical ingredients attributed to a set of biological properties, which include antibacterial, antifungal, antiviral, antioxidant, anticancer, immune-modulatory, analgesic and anti-inflammatory activities. Their use in pharmaceutics is however compromised by their limited water solubility and low physicochemical stability (i.e. volatility, oxidation). In order to overcome these limitations, we aimed to develop nanostructured lipid carriers (NLC) as delivery systems for Mediterranean essential oils, in particular Rosmarinus officinalis L., Lavandula x intermedia "Sumian", Origanum vulgare subsp. hirtum and Thymus capitatus essential oils, selected on the basis of their antioxidant and anti-inflammatory activities. NLC composed of Softisan (as solid lipid) have been produced by phase inversion temperature (PIT) and high-pressure homogenization (HPH), using two different emulsifiers systems. Particles have been further characterized for their mean particle size, polydispersity, zeta potential, morphology and chemical interactions. Best NLC formulations were obtained with Kolliphor/Labrafil as surfactants, and using Rosmarinus, Lavandula and Origanum as essential oils (PDI between 0.126 and 0.141, Zave < 200 nm). Accelerated stability studies have also been carried out to estimate the effect of the production method and surfactant composition on the long-term stability of EOs-loaded NLC. In vitro biological cell viability and anti-inflammatory activities were evaluated in Raw 264.7 cells (macrophage cell line), while in vitro antioxidant activity was checked by DPPH assay. Lavandula and Rosmarinus NLC were shown to be the most biocompatible formulations up to a concentration of 0.1% (v/v), whereas they were able to induce a dose-dependent anti-inflammatory activity in the order Lavandula > Rosmarinus ≥ Origanum.


Subject(s)
Lavandula , Oils, Volatile , Origanum , Rosmarinus , Animals , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/chemistry , Antioxidants/administration & dosage , Antioxidants/chemistry , Biphenyl Compounds/chemistry , Cell Survival , Lipids/administration & dosage , Lipids/chemistry , Lipopolysaccharides/pharmacology , Mice , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Nitric Oxide/metabolism , Oils, Volatile/administration & dosage , Oils, Volatile/chemistry , Picrates/chemistry , RAW 264.7 Cells
20.
Colloids Surf B Biointerfaces ; 167: 337-344, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29684903

ABSTRACT

In this work, we aimed at developing an improved topical SLN formulation combining itraconazole delivery with a coating layer of didodecyldimethylammonium bromide, thus repurposing the drug effectiveness by synergistic skin anticancer effectiveness. In order to obtain a stable SLN formulation with small homogeneously dispersed particles, a deep formulative study was developed screening three different solid lipids (Suppocire NB, Cetyl Palmitate and Dynasan 114) for the SLN preparation by the phase inversion temperature. A bluishcolored shade formulation, with homogeneous small particles size (<50 nm) was obtained only using Suppocire NB. The cytotoxicity of all SLN was tested after 24 h exposure against three adherent skin cell lines (A431, HaCaT and SK-MEL-5). Results demonstrate that both unloaded and drugloaded SLN did not significantly affect the cell viability of the non-tumoral HaCaT cell line, thus confirming the safe potential topical application of these formulations. A dose-dependent decrease in cell viability was observed for the tumoral cell lines, A431 and SK-MEL-5, with a significant reduction of the A431 cancer cell line viability. The drug molecule addition to the uncoated nanoparticles was able to increase of almost 20% the reduction of the viability of the cancer cells treated. Ours results demonstrate the potentiality of repurposing itraconazole activity by using the combined nanoencapsulation strategy with the positively charged coating layer on SLN, which can be further investigated as a promising stable and safe approach to significantly reduce the viability of skin cancer cells.


Subject(s)
Antineoplastic Agents/pharmacology , Azoles/chemistry , Drug Repositioning , Itraconazole/pharmacology , Lipids/chemistry , Nanoparticles/chemistry , Quaternary Ammonium Compounds/chemistry , Skin Neoplasms/drug therapy , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Drug Delivery Systems , Drug Screening Assays, Antitumor , Humans , Itraconazole/chemistry , Particle Size , Skin Neoplasms/pathology , Structure-Activity Relationship , Surface Properties
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