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1.
Front Med (Lausanne) ; 11: 1400423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835799

RESUMO

Hansen's disease, or leprosy, is a disease characterized by dermatological and neurological disorders. A neural form also exists, in which peripheral neuropathy occurs in the absence of skin lesions. However, cases of leprosy that involve the central nervous system and proximal nerves are rare in the literature. We describe the case of an oligosymptomatic patient diagnosed with the neural form of leprosy with involvement of peripheral nerves, dorsal root ganglion, and cervical spinal cord in an atypical presentation of the disease. Through complementary examinations and nerve biopsies, the bacillus was identified, and treatment was subsequently initiated. This case highlights the importance of investigating the suspicion of leprosy, even in cases with atypical manifestations, as early diagnosis and treatment can reduce neurological damage and deformities.

2.
Front Immunol ; 14: 1272471, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116016

RESUMO

Introduction: Pure Neural Leprosy (PNL) is a form of this long time known disease that affects only the peripheral nervous system. Since it is a rare form of the disease, its pathophisiology is still poorly understood. Objective: Describe the cytokines profile in patients with PNL. Methods: 30 Patients diagnosed with PNL in the Souza Araujo Outpatient Clinic and with cytokines evaluated were selected. They were evaluated by neurologists and diagnosed after a nerve biopsy. Serum levels of IL-1 ß, IL-6, IL-10, IL-17, TNF, CCL-2/MCP-1, IFN-ϒ, CXCL-10/IP-10 and TGF-ß were evaluates at the moment of the diagnosis. Results: Neural thickening was a common clinical finding in this groups of patients. Small and medium sensitive fibers signs and symptoms were present in 92% of the patients and motor involvement in 53%. 43% of patients presented neuropathic pain and no one had neuritis TGF-beta, IL-17, CCl-2 and IP-10. CCL-2 levels were associated with demyelinating patters and IP-10 and IL-1o were associated with axonal patterns at NCS. Discussion: PNL patients' cytokine profile appears to be different of other clinical forms of leprosy, with the presence of cytokines described in both tuberculoid and lepromatous leprosy. High levels of CCl-2 may be related to the presence of silent neuritis as well as the presence of IL-10. PNL is unique a form of leprosy, therefore, understanding its immunological profiles essential to better understand the disease itself.


Assuntos
Hanseníase Tuberculoide , Hanseníase , Neurite (Inflamação) , Humanos , Hanseníase Tuberculoide/diagnóstico , Hanseníase Tuberculoide/patologia , Citocinas , Interleucina-10 , Interleucina-17 , Quimiocina CXCL10 , Fator de Crescimento Transformador beta
3.
Front Med (Lausanne) ; 10: 1202108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396908

RESUMO

One of the main manifestations of leprosy is peripheral nerve impairment. Early diagnosis and treatment are important to reduce the impact of neurological impairment, which can cause deformities and physical disabilities. Leprosy neuropathy can be acute or chronic, and neural involvement can occur before, during, or after multidrug therapy, and especially during reactional episodes when neuritis occurs. Neuritis causes loss of function in the nerves and can be irreversible if left untreated. The recommended treatment is corticosteroids, usually through an oral regimen at an immunosuppressive dose. However, patients with clinical conditions that restrict corticosteroid use or that have focal neural involvement may benefit from the use of ultrasound-guided perineural injectable corticosteroids. In this study, we report two cases that demonstrate how the treatment and follow-up of patients with neuritis secondary to leprosy, using new techniques, can be provided in a more individualized way. Nerve conduction studies in association with neuromuscular ultrasound were used to monitor the response to treatment with injected steroids, focusing on neural inflammation. This study provides new perspectives and options for this profile of patients.

4.
Front Med (Lausanne) ; 9: 865485, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402428

RESUMO

Introduction: Leprosy reactions are complications that can occur before, during, or after multidrug therapy (MDT) and are considered a major cause of nerve damage. Neuritis is an inflammatory process that causes nerve function impairment associated with pain and tenderness along the nerve. Neuritis can be found in both type 1 and type 2 reactions and may also be the sole manifestation of a leprosy reaction. The objective of this study is to describe the incidence of leprosy reactions and its association with neuropathic pain in pure neural leprosy (PNL) patients. Methods: We selected 52 patients diagnosed with PNL and 67 patients with other clinical forms of leprosy. During the MDT the patients visited the clinic monthly to take their supervised dose. The patients were instructed to return immediately if any new neurological deficit or skin lesions occurred during or after the MDT. Results: Of the PNL patients, 23.1% had a leprosy reaction during or after the MDT, while this was 59.7% for patients with the other clinical forms of leprosy. There was an association between having PNL and not having any reaction during and after the MDT, as well as having PNL and having neuritis after the MDT.There was also an association between having previous neuritis and having neuropathic pain in the other clinical forms of leprosy group, although this association was not present in the PNL group. Discussion: Our data suggest that PNL is a different form of the disease, which is immunologically more stable. In addition, PNL patients have more neuritis than the classical leprosy skin reactions. In PNL there was no association between acute neuritis and neuropathic pain, suggesting that these patients may have had silent neuritis. Understanding and identifying neuritis is essential to reduce disability and the impact on public health.

5.
PLoS Negl Trop Dis ; 16(1): e0010070, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35015773

RESUMO

INTRODUCTION: Pure Neural Leprosy (PNL) is a rare clinical form of leprosy in which patients do not present with the classical skin lesions but have a high burden of the disability associated with the disease. Clinical characteristics and follow up of patients in PNL are still poorly described in the literature. OBJECTIVE: This paper aims to describe the clinical, electrophysiological and histopathological characteristics of PNL patients, as well as their evolution after multidrug therapy (MDT). METHODS: Fifty-two PNL patients were selected. Clinical, nerve conduction studies (NCS), histopathological and anti-PGL-1serology were evaluated. Patients were also assessed monthly during the MDT. At the end of the MDT, all of the patients had a new neurological examination and 44 were submitted to another NCS. RESULTS: Paresthesia was the complaint most frequently reported by patients, and in the neurological examination the most common pattern observed was impairment in sensory and motor examination and a mononeuropathy multiplex. Painful nerve enlargement, a classical symptom of leprosy neuropathy, was observed in a minority of patients and in the motor NCS axonal injuries, alone or in combination with demyelinating features, were the most commonly observed. 88% of the patients did not present any leprosy reaction during MDT. There was no statistically significant difference between the neurological examinations, nor the NCS pattern, performed before and after the MDT. DISCUSSION: The classical hallmarks of leprosy neuropathy are not always present in PNL making the diagnosis even more challenging. Nerve biopsy is an important tool for PNL diagnosis as it may guide therapeutic decisions. This paper highlights unique characteristics of PNL in the spectrum of leprosy in an attempt to facilitate the diagnosis and management of these patients.


Assuntos
Hanseníase Tuberculoide/diagnóstico , Hanseníase Tuberculoide/patologia , Condução Nervosa/fisiologia , Polineuropatias/diagnóstico , Brasil , Quimioterapia Combinada , Feminino , Humanos , Hansenostáticos/uso terapêutico , Hanseníase Tuberculoide/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/isolamento & purificação , Parestesia/patologia , Polineuropatias/microbiologia , Polineuropatias/patologia
6.
Drug Deliv Transl Res ; 12(3): 526-537, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33682031

RESUMO

Transdermal administration of raloxifene hydrochloride (RLX)-loaded nanostructured lipid carriers (NLCs) has been proposed to circumvent its low oral bioavailability (2%). Preformulation studies were carried out to evaluate drug-excipient compatibility of various adjuvants commonly used for NLC preparation (waxes, cholesterol, compritol, gelucire, span 60, span 80, span 85, tween 80, poloxamer 188, oleic acid, caprylic/capric triglyceride, and castor oil). It was used differential scanning calorimetry (DSC), isothermal stress testing (IST), and solubility studies. The most promising excipients were chosen for NLC obtention, and full characterization was done, including in vitro skin permeation. DSC curves suggested drug-excipient interaction among some compounds, and the IST study showed incompatibility of RLX with waxes, compritol, cholesterol, span 60, and poloxamer 188. Solubility studies helped select gelucire, caprylic/capric triglyceride, span 80, and tween 80 for NLC production. Twelve NLCs were obtained (NLC1 to NLC12), but NLC7 and NLC8 were the most promising ones. In vitro release studies demonstrated that NLC7 and NLC8 were able to control RLX release (14.74 and 9.07% at 24 h, respectively) compared with the unloaded drug (> 90% at 24 h). Unloaded RLX did not permeate the diffusion cells' receptor medium and showed higher drug skin retention (11-fold) than RLX-loaded NLC. NLC reduced RLX skin retention, favoring drug permeation to deeper skin layers. NLC7 increased drug flux is 2.4-fold. NLC7 is a promising formulation for RLX transdermal drug delivery.


Assuntos
Nanopartículas , Nanoestruturas , Administração Cutânea , Portadores de Fármacos/química , Excipientes/química , Lipossomos , Nanopartículas/química , Tamanho da Partícula , Poloxâmero , Polissorbatos , Cloridrato de Raloxifeno , Triglicerídeos , Ceras
7.
Eur J Pharm Sci ; 168: 106048, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699938

RESUMO

Nanostructured lipid carriers (NLC)-loaded with lopinavir (LPV) were developed for its iontophoretic transdermal delivery. Electronic paramagnetic resonance (EPR) spectroscopy of fatty acid spin labels and differential scanning calorimetry (DSC) were applied to investigate the lipid dynamic behavior of NLC before and after the electrical current. In vitro release and permeation studies, with and without anodic and cathodic iontophoresis were also performed. NLC-LPV had nanometric size (179.0 ± 2.5 nm), high drug load (∼x223C 4.14%) and entrapment efficiency (EE) (∼x223C 80%). NLC-LPV was chemically and physically stable after applying an electric current. The electrical current reduced EE after 3 h (67.21 ± 2.64%), resulting in faster LPV in vitro release. EPR demonstrated that iontophoresis decreased NLC lipid dynamics, which is a long-lasting effect. DSC studies demonstrated that electrical current could trigger the polymorphic transition of NLC and drug solubilization in the lipid matrix. NLC-LPV, combined with iontophoresis, allowed drug quantification in the receptor medium, unlike unloaded drugs. Cathodic iontophoresis enabled the quantification of about 7.9 µg/cm2 of LPV in the receptor medium. Passive NLC-LPV studies had to be done for an additional 42 h to achieve similar concentrations. Besides, anodic iontophoresis increased by 1.8-fold the amount of LPV in the receptor medium, demonstrating a promising antiviral therapy strategy.


Assuntos
Nanopartículas , Nanoestruturas , Portadores de Fármacos , Iontoforese , Lipídeos , Lipossomos , Lopinavir , Tamanho da Partícula , Absorção Cutânea
8.
BMC Infect Dis ; 21(1): 858, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34425777

RESUMO

BACKGROUND: Diagnosing neuritis in leprosy patients with neuropathic pain or chronic neuropathy remains challenging since no specific laboratory or neurophysiological marker is available. METHODS: In a cross-sectional study developed at a leprosy outpatient clinic in Rio de Janeiro, RJ, Brazil, 54 individuals complaining of neural pain (single or multiple sites) were classified into two groups ("neuropathic pain" or "neuritis") by a neurological specialist in leprosy based on anamnesis together with clinical and electrophysiological examinations. A neurologist, blind to the pain diagnoses, interviewed and examined the participants using a standardized form that included clinical predictors, pain features, and neurological symptoms. The association between the clinical predictors and pain classifications was evaluated via the Pearson Chi-Square or Fisher's exact test (p < 0.05). RESULTS: Six clinical algorithms were generated to evaluate sensitivity and specificity, with 95% confidence intervals, for clinical predictors statistically associated with neuritis. The most conclusive clinical algorithm was: pain onset at any time during the previous 90 days, or in association with the initiation of neurological symptoms during the prior 30-day period, necessarily associated with the worsening of pain upon movement and nerve palpation, with 94% of specificity and 35% of sensitivity. CONCLUSION: This algorithm could help physicians confirm neuritis in leprosy patients with neural pain, particularly in primary health care units with no access to neurologists or electrophysiological tests.


Assuntos
Hanseníase , Neuralgia , Neurite (Inflamação) , Brasil , Regras de Decisão Clínica , Estudos Transversais , Humanos , Hanseníase/complicações , Hanseníase/diagnóstico , Neurite (Inflamação)/diagnóstico
9.
J Microencapsul ; 38(2): 124-133, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33305646

RESUMO

The study aimed to develop lipid nanoparticles using excipients compatible with carvedilol (CARV) for enhanced transdermal drug delivery. Nanostructured lipid carriers (NLC) were successfully obtained and fully characterised. Franz diffusion cells were used for release and in vitro permeation studies in the porcine epidermis (EP) and full-thickness rat skin. NLC4 and NLC5 (0.5 mg/mL of CARV) presented small size (80.58 ± 1.70 and 116.80 ± 12.23 nm, respectively) and entrapment efficiency of 98.14 ± 0.79 and 98.27 ± 0.99%, respectively. CARV-loaded NLC4 and NLC5 controlled drug release. NLC4 allowed CAR permeation through porcine EP in greater amounts than NLC5, i.e. 11.83 ± 4.71 µg/cm2 compared to 3.06 ± 0.79 µg/cm2. NLC4 increased CARV permeation by 2.5-fold compared to the unloaded drug in rat skin studies (13.73 ± 4.12 versus 5.31 ± 1.56 µg/cm2). NLC4 seems to be a promising carrier for the transdermal delivery of CARV.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Carvedilol/administração & dosagem , Portadores de Fármacos/química , Lipídeos/química , Administração Cutânea , Antagonistas Adrenérgicos beta/farmacocinética , Animais , Carvedilol/farmacocinética , Nanopartículas/química , Ratos , Ratos Wistar , Pele/metabolismo , Absorção Cutânea , Suínos
10.
Am J Trop Med Hyg ; 98(6): 1609-1613, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29611495

RESUMO

Neural pain is a frequent symptom in leprosy disease. There is a paucity of data regarding neural pain diagnostics resulting in common prescriptive errors when neuritis is confused with neuropathic or mixed nociceptive-neuropathic pain. The present study identified important demographic, clinical, and neurophysiological features of 42 leprosy neuropathy patients presenting neuropathic pain (NP). During routine evaluations, patients were selected asking if they had ever experienced neural pain. Data analyses of their pain characteristics, clinical examination results, and both the Douleur Neuropathique 4 Questionnaire and Hamilton Depression Scale scores were used to classify these patients. The most common word they used to describe the sensation of pain for 25 (60%) of these patients was "burning." In the early stages of the disease and before leprosy diagnosis, 19 (45%) had already complained about NP and leprosy treatment was unable to prevent its occurrence in 15 (36%). Leprosy reactions, considered NP risk factors, occurred in 32 (76%) cases. Knowledge of typical NP characteristics could be used to develop more effective therapeutic approaches for a notoriously difficult-to-treat pain condition.


Assuntos
Hanseníase/complicações , Neuralgia/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Hanseníase/epidemiologia , Hanseníase/fisiopatologia , Hanseníase Multibacilar/complicações , Hanseníase Multibacilar/epidemiologia , Hanseníase Multibacilar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos Motores/epidemiologia , Transtornos Motores/etiologia , Condução Nervosa/fisiologia , Neuralgia/epidemiologia , Neuralgia/etiologia , Dor , Medição da Dor , Transtornos de Sensação/epidemiologia , Transtornos de Sensação/etiologia , Adulto Jovem
11.
Int J Pharm ; 531(1): 292-298, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28859937

RESUMO

Voriconazole-loaded nanostructured lipid carriers (VOR-NLC) were developed and drug penetration evaluated in porcine hooves in vitro. Synergistic effect of urea (Ur), selected among other known chemical enhancers according to hoof hydration potential, was also evaluated. VOR-NLC presented a high encapsulation efficiency (74.52±2.13%), approximate mean diameter of 230nm and were positively charged (+27.32±2.74mV). Stability studies indicated they were stable under refrigeration (4±2°C) for up to 150days. SEM images revealed hooves treated with VOR-NLC and VOR-NLC-Ur suffered a disturbance on the surface depicting high roughness and porosity. Permeation data showed a substantial VOR amount retained in superficial hooves sections independent of the formulation used (2.42±0.26; 2.52±0.36 and 2.41±0.60µg/cm2 for unloaded VOR, VOR-NLC and VOR-NLC-Ur, respectively, p>0.05). Still, successive extractions, revealed the amount of VOR retained in deeper regions was significantly higher when VOR-NLC or VOR-NLC-Ur was used (0.17±0.04, 0.47±0.14 and 0.36±0.07µg/cm2 for unloaded VOR, VOR-NLC and VOR-NLC-Ur, respectively, p<0.05). Such results indicate NLC are promising formulations for the management of onychomycosis. Further studies in diseased nail plates are necessary.


Assuntos
Portadores de Fármacos/química , Lipídeos/química , Unhas/efeitos dos fármacos , Nanoestruturas/química , Voriconazol/administração & dosagem , Animais , Casco e Garras/efeitos dos fármacos , Humanos , Tamanho da Partícula , Suínos
12.
J Pharm Pharmacol ; 69(10): 1318-1326, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28703281

RESUMO

OBJECTIVES: This work aimed to evaluate semisolid formulations containing topotecan (TPT) loaded nanostructured lipid carriers (NLC) for topical treatment of skin cancers, as TPT is effective against a variety of tumours. A formulation which increases TPT skin permeation would be extremely desirable. METHODS: TPT-NLC were prepared and incorporated in hydrogels with hydroxyethyl cellulose and chitosan (TPT-NLC-HEC and TPT-NLC-Ch, respectively). Control formulations were obtained by dispersing TPT in HEC and Ch hydrogels (TPT-HEC and TPT-Ch). KEY FINDINGS: TPT-NLC-HEC and TPT-NLC-Ch showed to maintain the drug and nanoparticle dispersions stable for up to 30 days. When nanoparticles were incorporated into gels, TPT release was significantly decreased (P < 0.05). Still, TPT-NLC-HEC increased 2.37 times permeation compared with TPT-HEC (11.9 and 5.0 µg/cm2 , respectively). Cell culture experiments with B16F10 melanoma demonstrated that nanoencapsulation significantly increased TPT cytotoxicity (P < 0.05). TPT-NLC was more toxic than free TPT, with IC50 value of 5.74 µg/ml, whereas free TPT had an IC50 > 20 µg/ml. As skin permeated values of TPT from developed formulation (TPT-NLC) were superior to melanoma IC50, it can be extrapolated that chemotherapeutic permeated amounts may be sufficient for a therapeutic effect. CONCLUSIONS: TPT-NLC-HEC may be a valuable tool for the topical treatment of skin cancers.


Assuntos
Portadores de Fármacos/administração & dosagem , Melanoma Experimental/tratamento farmacológico , Nanopartículas/administração & dosagem , Absorção Cutânea/fisiologia , Neoplasias Cutâneas/tratamento farmacológico , Topotecan/administração & dosagem , Administração Tópica , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Portadores de Fármacos/metabolismo , Hidrogéis/administração & dosagem , Hidrogéis/metabolismo , Lipídeos/administração & dosagem , Melanoma Experimental/metabolismo , Camundongos , Nanopartículas/metabolismo , Técnicas de Cultura de Órgãos , Absorção Cutânea/efeitos dos fármacos , Neoplasias Cutâneas/metabolismo , Suínos , Inibidores da Topoisomerase I/administração & dosagem , Inibidores da Topoisomerase I/metabolismo , Topotecan/metabolismo , Resultado do Tratamento
13.
Planta Med ; 83(18): 1431-1437, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28651288

RESUMO

The topical application of Centella asiatica extract has been commonly used for many different purposes but especially for cosmetic use in the treatment of gynoid lipodystrophy. Asiaticoside, the most active component in this extract, is responsible for its therapeutic activities. However, little is known to date about asiaticoside skin penetration. Thus, an analytical method for asiaticoside quantification in different skin layers after the topical application of C. asiatica extract was developed and skin permeation studies were performed with the plant extract to apply the analytical method developed. An extraction procedure to recover asiaticoside from the biological matrix was also developed. Asiaticoside was assayed by HPLC/UV (high-performance liquid chromatography-ultraviolet detection) using a gradient of ACN (acetonitrile) and 0.2% phosphoric acid (flow rate of 1.0 mL/min). The analytical procedure was validated according to U. S. Food and Drug Administration guidelines. Selectivity was shown, as endogenous skin components did not interfere with the asiaticoside peak. Analytical curve was linear (3 to 60 µg/mL) and the lower limit of quantification was determined (3 µg/mL). Asiaticoside recoveries from skin samples were 95.1% and 66.7% for the stratum corneum and remaining skin, respectively. After 48 h of in vitro permeation studies, a substantial amount of asiaticoside was quantified in the skin layers. The presence of asiaticoside was also detected in the receptor solution of Franz diffusion cells after 48 h (5.81 ± 1.00 µg/mL). The method was reliable and reproducible for asiaticoside quantification in skin samples, thereby making it possible to determine the cutaneous penetration profile of this drug in permeation studies.


Assuntos
Centella/química , Cromatografia Líquida de Alta Pressão/métodos , Triterpenos/farmacocinética , Administração Cutânea , Extratos Vegetais , Pele/metabolismo , Absorção Cutânea , Triterpenos/química
14.
Eur J Pharm Biopharm ; 119: 142-149, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28627400

RESUMO

Combined therapy with corticosteroids and immunosuppressant-loaded nanostructured lipid carriers (NLC) could be useful in the treatment of skin diseases. To circumvent NLC loading capacity problems, loaded drugs should have different physicochemical characteristics, such as tacrolimus (TAC) and clobetasol (CLO). Therefore, in the present study, TAC and CLO were encapsulated in NLC (TAC-NLC, CLO-NLC and TAC+CLO-NLC), coated or otherwise with chitosan. Electron paramagnetic resonance (EPR) spectroscopy of different spin labels was used to investigate the impact of drug and oil incorporation on the lipid dynamic behavior of the lipid matrices. In addition, the impact of co-encapsulation on drug release and skin permeation was evaluated. Entrapment efficiency was greater than 90% for both drugs, even when the maximum drug loading achieved for TAC-NLC and CLO-NLC was kept at TAC+CLO-NLC, because TAC is more soluble in the solid lipid and CLO in the liquid lipid. EPR data indicated that both drugs reduced the lipid fluidity near the polar surface of the lipid matrix, which suggests their presence in this region. In addition, EPR data showed that liquid lipid is also present in more superficial regions of the nanoparticle matrix. CLO was released faster than TAC from TAC+CLO-NLC, probably because it is more soluble in the liquid lipid. TAC skin penetration was affected by CLO. A 5-fold increase in TAC penetration was observed from TAC+CLO-NLC when compared to TAC-NLC formulations. Coating also increased TAC and CLO permeation to deeper skin layers (1.8-fold and 1.6-fold, respectively). TAC+CLO-NLC seems to be an effective strategy for topical delivery of TAC and CLO, and thus constitutes promising formulations for the treatment of skin diseases.


Assuntos
Clobetasol/metabolismo , Portadores de Fármacos/metabolismo , Nanopartículas/metabolismo , Absorção Cutânea/fisiologia , Tacrolimo/metabolismo , Administração Cutânea , Animais , Clobetasol/administração & dosagem , Clobetasol/síntese química , Cultura em Câmaras de Difusão , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/síntese química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Lipídeos/administração & dosagem , Lipídeos/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Absorção Cutânea/efeitos dos fármacos , Suínos , Tacrolimo/administração & dosagem , Tacrolimo/síntese química
15.
Cornea ; 35(6): 866-71, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27055213

RESUMO

PURPOSE: To design and evaluate the potential of a topical delivery system for ocular administration of voriconazole, based on cationic nanostructured lipid carriers (NLCs). METHODS: NLC dispersions composed of glyceryl behenate/capric caprylic triglyceride, polysorbate 80, sorbitan trioleate, and cetylpyridinium chloride were obtained and characterized. Ex vivo permeations experiments were performed to evaluate their drug delivery potential. RESULTS: NLCs presented a mean diameter of 250.2 ± 03.1 nm, narrow polydispersity index (0.288 ± 0.03), positive zeta potential (31.22 ± 3.8 mV), and over 75% encapsulation efficiency. Ex vivo ocular experiments proved that NLCs were able to deliver therapeutically relevant drug amounts to the cornea after only 30 minutes (13.88 ± 0.24 µg/cm). CONCLUSIONS: The formulation was nonexpensive, easy to prepare, and composed of well-tolerated and accepted excipients. Further in vivo experiments are necessary to confirm the improved performance and tolerability of the formulation.


Assuntos
Antifúngicos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Lipídeos/química , Nanoestruturas , Voriconazol/administração & dosagem , Animais , Antifúngicos/farmacocinética , Antifúngicos/toxicidade , Química Farmacêutica , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Córnea/metabolismo , Nanopartículas , Nanoestruturas/química , Tamanho da Partícula , Suínos , Voriconazol/farmacocinética , Voriconazol/toxicidade
16.
J Pharm Pharmacol ; 68(6): 742-50, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27061573

RESUMO

OBJECTIVES: The aim of this study was to investigate in vitro the epidermal targeting potential of clobetasol propionate-loaded nanostructured lipid carriers (CP-NLC) when compared to that of chitosan-coated (CP-NLC-C). METHODS: CP-NLC were prepared by microemulsion method and characterized by dynamic light scattering, transmission electron microscopy, in vitro release and permeation studies. To verify epidermal targeting, permeation studies were performed in two sets of experiments. For the first set, the skin was removed from the diffusion cell and stratum corneum (SC) was separated from the remaining skin (RS). For the second set, the whole epidermis (EP) was separated from the dermis (DER). CP quantification was performed in each skin layer. KEY FINDINGS: A novel clobetasol propionate-loaded NLC was produced with 1/5th of the drug dose used in commercial formulations and, even so, presented greater skin permeation. Both chitosan-coated and uncoated NLC enhanced the amount of CP in the epidermis more than 80-fold when compared to the commercial formulation (20.26 ± 2.77; 17.85 ± 0.49 and 0.22 ± 0.02 µg/cm(2) , respectively). Differently from chitosan-coated NLC, the uncoated NLC did not show dermal retention. CONCLUSIONS: NLC proved to be a system with potential for targeting drug delivery to the epidermal layer.


Assuntos
Clobetasol/administração & dosagem , Portadores de Fármacos , Epiderme/metabolismo , Glucocorticoides/administração & dosagem , Lipídeos/química , Nanopartículas , Absorção Cutânea , Administração Cutânea , Animais , Quitosana/química , Clobetasol/química , Clobetasol/metabolismo , Composição de Medicamentos , Glucocorticoides/química , Glucocorticoides/metabolismo , Técnicas In Vitro , Cinética , Nanotecnologia , Permeabilidade , Solubilidade , Suínos , Tecnologia Farmacêutica/métodos
17.
Eur J Pharm Biopharm ; 88(1): 40-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24816130

RESUMO

The aim of this study was to develop lipid nanoparticles to deliver genistein (GEN) to deeper skin layers. To do so, the impact of lipid dynamic behavior (nanoparticle flexibility) on stability, release and skin permeation studies was verified. GEN-loaded solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) were obtained and characterization was undertaken. Freshly prepared nanoparticles were produced with similar features (i.e., drug loading). However, a higher level of crystallization in GEN-SLN formulation was observed in differential scanning calorimetry experiments. Electron paramagnetic resonance measurements showed a lower mobility of the spin labels in the SLN, which would indicate that NLC could be more flexible than SLN. Despite the fact that NLC demonstrated more fluidity, GEN was released more slowly from NLC than from SLN. Skin permeation studies demonstrated that lipid nanoparticles increased GEN skin retention. More flexible particles (NLC) also favored drug penetration into deeper skin layers. GEN-NLC would seem to be a promising formulation for GEN topical delivery.


Assuntos
Genisteína/administração & dosagem , Lipídeos/química , Nanopartículas/química , Pele/efeitos dos fármacos , Administração Cutânea , Animais , Varredura Diferencial de Calorimetria , Química Farmacêutica , Portadores de Fármacos/química , Orelha Externa/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Tamanho da Partícula , Absorção Cutânea , Suínos
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