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1.
Entropy (Basel) ; 26(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38248176

RESUMEN

Change points indicate significant shifts in the statistical properties in data streams at some time points. Detecting change points efficiently and effectively are essential for us to understand the underlying data-generating mechanism in modern data streams with versatile parameter-varying patterns. However, it becomes a highly challenging problem to locate multiple change points in the noisy data. Although the Bayesian information criterion has been proven to be an effective way of selecting multiple change points in an asymptotical sense, its finite sample performance could be deficient. In this article, we have reviewed a list of information criterion-based methods for multiple change point detection, including Akaike information criterion, Bayesian information criterion, minimum description length, and their variants, with the emphasis on their practical applications. Simulation studies are conducted to investigate the actual performance of different information criteria in detecting multiple change points with possible model mis-specification for the practitioners. A case study on the SCADA signals of wind turbines is conducted to demonstrate the actual change point detection power of different information criteria. Finally, some key challenges in the development and application of multiple change point detection are presented for future research work.

2.
Eur J Oper Res ; 304(1): 308-324, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34848917

RESUMEN

The global health crisis caused by the coronavirus SARS-CoV-2 has highlighted the importance of efficient disease detection and control strategies for minimizing the number of infections and deaths in the population and halting the spread of the pandemic. Countries have shown different preparedness levels for promptly implementing disease detection strategies, via mass testing and isolation of identified cases, which led to a largely varying impact of the outbreak on the populations and health-care systems. In this paper, we propose a new pandemic resource allocation model for allocating limited disease detection and control resources, in particular testing capacities, in order to limit the spread of a pandemic. The proposed model is a novel epidemiological compartmental model formulated as a non-linear programming model that is suitable to address the inherent non-linearity of an infectious disease progression within the population. A number of novel features are implemented in the model to take into account important disease characteristics, such as asymptomatic infection and the distinct risk levels of infection within different segments of the population. Moreover, a method is proposed to estimate the vulnerability level of the different communities impacted by the pandemic and to explicitly consider equity in the resource allocation problem. The model is validated against real data for a case study of COVID-19 outbreak in France and our results provide various insights on the optimal testing intervention time and level, and the impact of the optimal allocation of testing resources on the spread of the disease among regions. The results confirm the significance of the proposed modeling framework for informing policymakers on the best preparedness strategies against future infectious disease outbreaks.

3.
Haemophilia ; 28(2): 230-238, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35060242

RESUMEN

INTRODUCTION: The large interpatient variability in the pharmacokinetic (PK) parameters of recombinant Factor VIII (rFVIII) observed in haemophilia A hinders efficient and cost-beneficial prophylactic regimen initiation. Identification of factors influencing the PK of rFVIII may shed more light on personalised treatment. AIM: This study aimed to develop a population PK model in the Taiwanese haemophilia A and evaluate the current national health insurance (NHI) reimbursement guidelines of Taiwan for haemophilia treatment. METHODS: A population PK analysis was established based on 69 Taiwanese with moderate or severe haemophilia A. A nonlinear mixed-effects modelling (NONMEM® ) was used to estimate PK parameters and their variabilities. A Monte Carlo simulation was performed to evaluate different prophylactic regimens. RESULTS: A two-compartment model with first-order elimination best described the rFVIII data. Weight-based allometric scaling was related to clearance and central volume of distribution. Blood type and baseline von Willebrand factor (VWF) were significant covariates for clearance. For single dose simulations, a time achieving target level (> 1 IU/dL) was associated with increasing rFVIII dose and VWF level. The multiple dose simulations showed that > 96.4% of patients with high VWF level (> 200%) had predicted trough level > 1 IU/dL for all dosing regimens (15-40 IU/kg, two to three times weekly). However, for twice weekly dosing, lower percentage (47.62-62.20%) of patients with blood group O and low VWF level (< 50%) achieved a predicted trough level > 1 IU/dL. CONCLUSION: The population PK of rFVIII was successfully developed. Dose adjustment based on blood type and VWF level should be considered.


Asunto(s)
Antígenos de Grupos Sanguíneos , Hemofilia A , Enfermedades de von Willebrand , Factor VIII/farmacocinética , Hemofilia A/tratamiento farmacológico , Humanos , Enfermedades de von Willebrand/tratamiento farmacológico , Factor de von Willebrand/farmacocinética
4.
BMC Cardiovasc Disord ; 19(1): 188, 2019 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-31382884

RESUMEN

BACKGROUND: Coronary artery aneurysm (CAA) is a rare disease, and there are limited data on prescribing patterns for CAA. The aim of our study was to investigate prescribing patterns for CAA in Taiwan via the National Health Insurance Research Database (NHIRD). METHODS: We included all CAA patients in Taiwan from 2005 to 2011. Data from 1 year before and after the CAA diagnosis were used to analyze examinations, comorbidities and prescribing patterns. RESULTS: A total of 1397 patients diagnosed with CAA were enrolled in our study. Most pediatric patients with CAA were diagnosed with Kawasaki disease (95.7%). In pediatric CAA patients, the utilization rates of aspirin and gamma globulins were 82.9 and 53.6%, respectively, after CAA diagnosis. Among the antithrombotic agents, aspirin was used most commonly, followed by dipyridamole (16.9%), heparin (5.8%) and warfarin (4.6%). In adult CAA patients, common comorbidities included hypertension (63.4%), hyperlipidemia (39.6%), and diabetes mellitus (26.1%). Coronary atherosclerosis was identified in 72.5% of adult patients after CAA diagnosis. Antithrombotic agents, particularly aspirin, clopidogrel and heparin, were prescribed more frequently after CAA diagnosis. Among the prescribed medications, aspirin (75.8%), ß-blockers (48.3%), statins (47.6%), metformin (14.4%), sulfonylureas (14.4%) and isosorbide mononitrate (32.9%) were frequently observed in each category. CONCLUSIONS: Kawasaki disease was the main cause of CAA in pediatric patients, and coronary artery disease was the most common comorbidity in adult CAA patients. The most commonly used antithrombic agent after CAA diagnosis was aspirin in both adult and pediatric patients.


Asunto(s)
Fármacos Cardiovasculares/uso terapéutico , Aneurisma Coronario/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Pautas de la Práctica en Medicina/tendencias , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Preescolar , Comorbilidad , Aneurisma Coronario/diagnóstico por imagen , Aneurisma Coronario/epidemiología , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Bases de Datos Factuales , Prescripciones de Medicamentos , Utilización de Medicamentos/tendencias , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Taiwán/epidemiología , Factores de Tiempo , Adulto Joven
5.
Risk Anal ; 39(9): 1949-1969, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30779857

RESUMEN

This article proposes a novel mathematical optimization framework for the identification of the vulnerabilities of electric power infrastructure systems (which is a paramount example of critical infrastructure) due to natural hazards. In this framework, the potential impacts of a specific natural hazard on an infrastructure are first evaluated in terms of failure and recovery probabilities of system components. Then, these are fed into a bi-level attacker-defender interdiction model to determine the critical components whose failures lead to the largest system functionality loss. The proposed framework bridges the gap between the difficulties of accurately predicting the hazard information in classical probability-based analyses and the over conservatism of the pure attacker-defender interdiction models. Mathematically, the proposed model configures a bi-level max-min mixed integer linear programming (MILP) that is challenging to solve. For its solution, the problem is casted into an equivalent one-level MILP that can be solved by efficient global solvers. The approach is applied to a case study concerning the vulnerability identification of the georeferenced RTS24 test system under simulated wind storms. The numerical results demonstrate the effectiveness of the proposed framework for identifying critical locations under multiple hazard events and, thus, for providing a useful tool to help decisionmakers in making more-informed prehazard preparation decisions.

6.
Biol Pharm Bull ; 36(2): 276-86, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23370356

RESUMEN

The aim of this study was to develop lipid nanocarriers that combine tretinoin and tetracycline for the efficient topical delivery to treat acne vulgaris. Two different nanocarriers, nanoemulsions (NEs) and nanostructured lipid carriers (NLCs), were prepared, and we examined their average size, zeta potential, drug encapsulation percentage, and drug permeation via the skin. The antibacterial activities of the nanosystems against Staphylococcus aureus, Pseudomonas aeruginosa, and Propionibacterium acnes were evaluated by an agar diffusion assay and the amount of total protein. A ca. 200-nm particle size was achieved with the prepared nanoparticles. The size increased when incorporating a cationic surfactant. Dual-drug loading did not largely affect the size of negatively charged nanoparticles, but significantly reduced the particle size of positively charged nanocarriers. NEs and NLCs exhibited high entrapment of tretinoin which ranged 60-100%. Tetracycline mainly resided in the aqueous phase, with ca. 10% of molecules located at the particulate interface. An in vitro skin permeation study showed that NLCs enhanced tetracycline flux by about 2-times over the control solution. Tretinoin permeation was generally unaffected after nanoparticulate encapsulation. There was no significant difference in tretinoin delivery before or after tetracycline incorporation, while tetracycline permeation significantly decreased by 2-fold in the dual-drug system. Nanoparticulate loading mostly maintained the antibacterial activity of tetracycline. Negatively charged NEs and NLCs even strengthened the antibacterial ability against S. aureus compared to the control solution. This is the first report examining skin permeation and antibacterial activities of dual-drug nanocarriers for acne treatment.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Antibacterianos/administración & dosificación , Portadores de Fármacos/administración & dosificación , Queratolíticos/administración & dosificación , Tetraciclina/administración & dosificación , Tretinoina/administración & dosificación , Administración Tópica , Animales , Antibacterianos/química , Portadores de Fármacos/química , Emulsiones , Femenino , Queratolíticos/química , Lípidos/química , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/administración & dosificación , Nanopartículas/química , Propionibacterium acnes/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Piel/efectos de los fármacos , Piel/metabolismo , Absorción Cutánea , Staphylococcus aureus/efectos de los fármacos , Tetraciclina/química , Tretinoina/química
7.
Macromol Biosci ; 23(10): e2300145, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37279400

RESUMEN

Nanofiber meshes (NFMs) loaded with therapeutic agents are very often employed to treat hard-to-heal wounds such as diabetic wounds. However, most of the NFMs have limited capability to load multiple or hydrophilicity distinctive-therapeutic agents. The therapy strategy is therefore significantly hampered. To tackle the innate drawback associated with the drug loading versatility, a chitosan-based nanocapsule-in-nanofiber (NC-in-NF) structural NFM system is developed for simultaneous loading of hydrophobic and hydrophilic drugs. Oleic acid-modified chitosan is first converted into NCs by the developed mini-emulsion interfacial cross-linking procedure, followed by loading a hydrophobic anti-inflammatory agent Curcumin (Cur) into the NCs. Sequentially, the Cur-loaded NCs are successfully introduced into reductant-responsive maleoyl functional chitosan/polyvinyl alcohol NFMs containing a hydrophilic antibiotic Tetracycline hydrochloride. Having a co-loading capability for hydrophilicity distinctive agents, biocompatibility, and a controlled release property, the resulting NFMs have demonstrated the efficacy on promoting wound healing either in normal or diabetic rats.

8.
Biomedicines ; 10(6)2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35740372

RESUMEN

Chemotherapy is the treatment of choice for gastric cancer; however, the currently available therapeutic drugs for treatment have limited efficacy. Cancer stemness and the tumor microenvironment may play crucial roles in tumor growth and chemoresistance. Glucose-regulated protein 78 (GRP78) is an endoplasmic reticulum chaperone facilitating protein folding and cell homeostasis during stress and may participate in chemoresistance. Isoliquiritigenin (ISL) is a bioactive flavonoid found in licorice. In this study, we demonstrated the role of GRP78 in gastric cancer stemness and evaluated GRP78-mediated stemness inhibition, tumor microenvironment regulation, and chemosensitivity promotion by ISL. ISL not only suppressed GRP78-mediated gastric cancer stem cell-like characteristics, stemness-related protein expression, and cancer-associated fibroblast activation but also gastric tumor growth in xenograft animal studies. The findings indicated that ISL is a promising candidate for clinical use in combination chemotherapy.

9.
Chem Pharm Bull (Tokyo) ; 59(2): 266-71, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21297310

RESUMEN

Tryptanthrin is an ancient medicine which recently was also found to have a function of downregulating multidrug resistance (MDR). However, tryptanthrin is insoluble in water, which limits its availability for delivery into cancer cells. There is a need to improve delivery systems to increase the inhibition of MDR. The aim of this study was to employ nanoparticles encapsulating tryptanthrin to improve the delivery and promote the sustained release of this drug. The approach was to encapsulate tryptanthrin in various nanoparticles, including solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), and lipid emulsions (LEs). We compared the particle size and zeta potential of these nanoparticles, and evaluated the partitioning behavior of tryptanthrin in them. We also determined the release kinetics of tryptanthrin from these nanoparticles. Moreover, cellular cytotoxicity toward and uptake of tryptanthrin-loaded nanoparticles by human breast cancer cells were determined. We found that the mean particle size of NLCs was lower, and the partition coefficient was higher than those of SLNs, and an increased tryptanthrin release rate was found with the NLC delivery system. NLCs achieved the sustained release of tryptanthrin without an initial burst. In particular, the NLC-C formulation, composed of a mixture of Compritol and squalene as the core materials, showed the highest release rate and cytotoxic effect. Confocal laser scanning microscopic images confirmed drug internalization into cells which enhanced the endocytosis of the particles. These results suggested that NLCs can potentially be exploited as a drug carrier for topical or intravenous use in the future.


Asunto(s)
Neoplasias de la Mama , Sistemas de Liberación de Medicamentos/métodos , Lípidos/administración & dosificación , Nanopartículas/administración & dosificación , Quinazolinas/administración & dosificación , Femenino , Humanos , Lípidos/química , Nanopartículas/química , Quinazolinas/química , Solubilidad/efectos de los fármacos , Células Tumorales Cultivadas
10.
Colloids Surf B Biointerfaces ; 202: 111658, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33677134

RESUMEN

TiO2 acts as an inorganic sunscreen and photocatalyst to protect humans from environmental pollutants. We incorporated TiO2 into mesoporous silica (SBA-15) for skin application to prevent environmental stresses including UVA irradiation and pollutant invasion. Organic ultraviolet (UV)A filters such as avobenzone and oxybenzone were then loaded into mesoporous support for synergistic sunscreen efficiency. The as-prepared formulations with different TiO2 amounts (10 %-50 %) were fabricated. The pore size decreased from 4.72 to 4.00 nm following the increase in TiO2 percentage. TiO2/SBA-15 captured about 60 % fluoranthene and 80 % furfural within 3 h with no significant difference due to different TiO2 content. The in vitro photoprotection assessed by UVA/UVB ratio exhibited the increase in Boots star rating from 2 to 3 to 5 by entrapment of avobenzone into TiO2/SBA-15. Thirty-percent TiO2/SBA-15 in hydrogel decreased avobenzone and oxybenzone deposition by 70 % and 80 % compared to free form, respectively. Avobenzone and TiO2 supplementation to SBA-15 significantly alleviated skin cell death and neutrophil recruitment in the photoaged mouse skin compared to the SBA-15 application alone. Compared to the UVA-irradiated skin, 30 % TiO2/SBA-15 showed a 2.5- and 3.1-fold decline in IL-1ß and IL-6 levels, respectively. The TiO2/SBA-15 hybrid was considered non-irritant based on results of cytotoxicity assay, skin histology, and cutaneous barrier function. Our data indicate that the versatile mesoporous silica is an effective system for topical use in sunscreen and skin protection.


Asunto(s)
Contaminantes Ambientales , Protectores Solares , Adsorción , Dióxido de Silicio , Piel , Protectores Solares/farmacología , Titanio , Rayos Ultravioleta
11.
Cancers (Basel) ; 12(9)2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32911820

RESUMEN

Lymph node metastasis is an aggressive condition characterized by poor treatment outcomes and low overall survival. Belinostat is a novel histone deacetylase (HDAC) inhibitor approved by the Food and Drug Administration (FDA) for the treatment of relapsed peripheral T-cell lymphoma (PTCL). However, the major problem is that belinostat has a short half-life of 1.1 h. In this study, we successfully prepared 50 nm liposomal colloids, which showed a controlled release pattern and excellent pharmacokinetics. The results showed that the particle size of liposomes consisting of dioleoylphosphatidylcholine (DOPC) was larger than that of those consisting of dioleoylglycerophosphoserine (DOPS). In terms of release kinetics of belinostat, the free drug was rapidly released and showed lower area under curve (AUC) exposure for in vivo pharmacokinetics. When liposomal formulations were employed, the release pattern was fitted with Hixson-Crowell models and showed sustained release of belinostat. Moreover, HuT-78 cells were able to take up all the liposomes in a concentration-dependent manner. The safety assessment confirmed hemocompatibility, and the platelet count was increased. Furthermore, the liposomes consisting of DOPC or DOPS had different behavior patterns, and their delivery to lymphatic regions should be thoroughly investigated in the future.

12.
Int J Nanomedicine ; 15: 1731-1743, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32210563

RESUMEN

BACKGROUND: Paclitaxel is wildly used in chemotherapy, however, the adverse drug reactions (ADRs) occurred frequently. Various novel nano-based paclitaxel delivery systems were developed. The aim performed systemically review and meta-analyses to evaluate the effect adverse drug reactions (ADRs) of paclitaxel and its nano-based delivery systems. METHODS: Systematically searched PubMed, Embase, Web of Science, Cochrane, Clinicalkey, Clinicaltrial.com, ASCO and ESMO. Data of adverse effect were analyzed to odds ratio (ORs) with 95% confidence interval (CI). The quality of studies was assessed with CASP Randomised Controlled Trial Checklist. Statistical analysis was used WinBUGS software (version 1.4.3) with the NetMetaXL interface (version 1.6.1). RESULTS: Twenty-one studies, including 7011 patients and 6 paclitaxel formulations fulfilled the inclusion criteria. In all grade hypersensitivity reactions, comparing to SB-P, people with Lip-P had 0.19 times (95% CI= 0.02, 1.3) of chance, with Nab-P had 0.47 times (95% CI= 0.11, 1.40) of chance, with PPX had 0.44 times (95% CI= 0.03, 5.7) of chance for all grade adverse effect. In All grad neutropenia, comparing to Lip-P, people with SB-P had 0.83 times (95% CI= 0.15, 4.81) of chance for all grade adverse effect; comparing to PM-P, people with SB-P had 0.73 times (95% CI= 0.22, 2.42) of chance for all grade adverse effect. In leucopenia, comparing to Nab-P, people with SB-P had 0.66 times (95% CI= 0.50, 0.87) of chance for all grade adverse effect; comparing to PM-P, people with SB-P had 0.64 times (95% CI= 0.32, 1.16) of chance for all grade adverse effect. The rate of incidence in peripheral sensory neuropathy, myalgias and arthralgias tend to no significant differences between different formulations. CONCLUSION: Nano-based paclitaxel delivery resulted in fewer hypersensitivity reactions than solvent-based delivery. However, the incidence of neutropenia and leucopenia was higher in nano-based than solvent-based paclitaxel delivery. Dose-dependent ADRs were more frequent in paclitaxel anticancer treatment.


Asunto(s)
Sistemas de Liberación de Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/tratamiento farmacológico , Nanopartículas/química , Paclitaxel/uso terapéutico , Femenino , Humanos , Hipersensibilidad/etiología , Masculino , Persona de Mediana Edad , Metaanálisis en Red
13.
Pharmaceutics ; 11(11)2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31683822

RESUMEN

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer with a worse prognosis than other types. There are currently no specific approved treatments for TNBC. Albumin is a promising biomimetic material that may be fabricated into nanoparticles to possibly exert passive effects on targeted tumors. Irinotecan has been extensively used in clinical settings, although a high dosage is required due to its low efficiency of conversion into the active metabolite SN-38, also known as 7-ethyl-10-hydroxy-camptothecin. The aim of this work was to optimize SN-38-loaded bovine serum albumin nanoparticles (sBSANPs) and evaluate their potency against TNBC. The sBSANPs were characterized by a small size of about 134-264 nm, a negative charge of -37 to -40 mV, an entrapment efficiency of 59-71%, and a particle yield of 65-86%. The cytotoxicity assays using sBSANPs showed a higher potency specifically against both MDA-MB-468 and MDA-MB-231 cells (ER-, PR-, HER2-) compared to MCF-7 (ER+, PR+, HER2-), and exhibited an extremely low IC50 at the nanomolar levels (2.01-6.82 nM). The release profiles indicated that SN-38 presented an initial burst release within 12 h, and sBSANPs had a slow release pattern. Flow cytometry results showed that the fluorescence intensity of sBSANPs was significantly higher than that of the control group. The confocal images also confirmed that sBSANPs were taken up by MDA-MB-468 cells. Moreover, we found that a larger BSANP size resulted in an increased hemolytic effect. In vivo animal studies demonstrated that loading of SN-38 into bovine serum albumin nanoparticles could minimize the initial concentration without extending the elimination half-life, but significantly minimized the Cmax (p < 0.001) as compared with irinotecan treatment.

14.
Int J Pharm ; 356(1-2): 144-52, 2008 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-18325699

RESUMEN

Topical photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an alternative therapy for many non-melanoma skin cancers. The major limitation of this therapy, however, is the low permeability of ALA through the stratum corneum (SC) of the skin. The objective of the present work was to characterize ethosomes containing ALA and to enhance the skin production of protoporphyrin IX (PpIX), compared to traditional liposomes. Results showed that the average particle sizes of the ethosomes were less than those of liposomes. Moreover, the entrapment efficiency of ALA in the ethosome formulations was 8-66% depending on the surfactant added. The particle size of the ethosomes was still approximately <200 nm after 32 days of storage. An in vivo animal study observed the presence of PpIX in the skin by confocal laser scanning microscopy (CLSM). The results indicated that the penetration ability of ethosomes was greater than that of liposomes. The enhancements of all the formulations were ranging from 11- to 15-fold in contrast to that of control (ALA in an aqueous solution) in terms of PpIX intensity. In addition, colorimetry detected no erythema in the irradiated skin. The results demonstrated that the enhancement ratio of ethosome formulations did not significantly differ between the non-irradiated and irradiated groups except for PE/CH/SS, which may have been due to a photobleaching effect of the PDT-irradiation process.


Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Etanol/química , Fármacos Fotosensibilizantes/administración & dosificación , Ácido Aminolevulínico/efectos adversos , Ácido Aminolevulínico/farmacocinética , Animales , Química Farmacéutica , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Femenino , Liposomas , Ratones , Ratones Endogámicos ICR , Ratones Desnudos , Tamaño de la Partícula , Permeabilidad , Fotoquimioterapia , Fármacos Fotosensibilizantes/efectos adversos , Fármacos Fotosensibilizantes/farmacocinética , Protoporfirinas/metabolismo , Absorción Cutánea , Neoplasias Cutáneas/tratamiento farmacológico , Tensoactivos/química
15.
J Liposome Res ; 18(1): 31-45, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18348070

RESUMEN

In this study we successfully entrapped 5-aminolevulinic acid (ALA) in liposome, although it exists as a zwitter ion. A molar ratio of 2:1:2.5 phosphatidyle-thanolamine (PE)/cholesterol/sodium stearate represented the best condition to achieve high entrapment efficiency (29.37 +/- 1.21%), and the average vehicle size was 133.6 +/- 2.8 nm. After 32 days of storage, the vehicle sizes of formulations with PE series were still approximately less than 200 nm. The safety of liposomes was tested and ensured both with regard to cellular cytotoxicity and erythrocyte hemolysis. Safety studies showed that liposome formulations did not affect cell viability except when both potassium stearate and sodium oleate were added. Moreover, PE and PE/cholesterol did not damage human erythrocytes in this study. The range of the hemolytic effect caused by liposomes was 5 to 37% and the effect was dependent on the amount of sodium stearate added to the formulation. According to the release rates and skin penetration of ALA liposomes in vitro, PE/cholesterol/sodium stearate liposomes might increase skin penetration, and it was shown that penetration across the stratum-corneum (sc) layer was the rate-limiting process. Images from confocal laser scanning microscopy (CLSM) confirmed the great potency of liposomes for delivering ALA into skin.


Asunto(s)
Ácido Aminolevulínico/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Liposomas/química , Piel/metabolismo , Animales , Colesterol/metabolismo , Fibroblastos/metabolismo , Humanos , Iones , Modelos Biológicos , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Seguridad , Piel/patología , Estearatos/química
16.
Drug Des Devel Ther ; 12: 159-169, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29391780

RESUMEN

INTRODUCTION: Mitomycin C is an anticancer antibiotic agent that has the potential for broad-spectrum use against several cancers, including mammary cancers. Because its half-life is 17 min after a 30 mg intravenous bolus administration, the suitability of mitomycin C for wide use in the clinical setting is limited. Based on tumor pathophysiology, pH-sensitive liposomes could provide better tumor-targeted effects. The aim of this study was to investigate the possibility of diminishing the side effect of mitomycin C by using pH-sensitive liposomes. MATERIALS AND METHODS: pH-sensitive liposomes was employed to deliver mitomycin C and evaluate the characterization, release behaviors, cytotoxicity, in vivo pharmacokinetics and biochemical assay. RESULTS: The results demonstrated that mitomycin C-loaded pH-sensitive liposomes had a particle diameter of 144.5±2.8 nm and an entrapment efficiency of 66.5%. The in vitro release study showed that the pH-sensitive liposome release percentages at pH 7.4 and pH 5.5 were approximately 47% and 93%, respectively. The cell viability of MCF-7 cells showed that both the solution and liposome group exhibited a concentration-dependent effect on cell viability. The MCF-7 cell uptake of pH-sensitive liposomes with a folate modification was higher which was indicated by an increased fluorescence intensity compared to that without a folate modification. The area under the concentration-time curve of mitomycin C-loaded pH-sensitive liposomes (18.82±0.51 µg·h/L) was significantly higher than that of the mitomycin C solution group (10.07±0.31 µg·h/L). The mean residence times of the mitomycin C-loaded and mitomycin C solution groups were 1.53±0.16 and 0.05 h, respectively. In addition, there was no significant difference in terms of Vss (p>0.05). Moreover, the half-life of pH-sensitive liposomes and the mitomycin C solution was 1.35±0.15 and 1.60±0.04 h, respectively. In terms of safety, mitomycin C-loaded pH-sensitive liposomes did not affect the platelet count and the levels of blood urea nitrogen and aspartate aminotransferase. CONCLUSION: The positive results of pH-sensitive liposomes demonstrated maintained the cytotoxicity and decrease the side effect.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Mitomicina/administración & dosificación , Mitomicina/efectos adversos , Animales , Antibióticos Antineoplásicos/farmacocinética , Supervivencia Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Estabilidad de Medicamentos , Ácido Fólico/metabolismo , Semivida , Humanos , Concentración de Iones de Hidrógeno , Liposomas , Células MCF-7 , Masculino , Mitomicina/farmacocinética , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley
17.
Colloids Surf B Biointerfaces ; 161: 121-128, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29055864

RESUMEN

The aim of the present study was to design a microemulsion for catechin topical application. A mixture experimental design with five independent variables (X1: oil, X2: surfactant, X3: catechin, X4: cosurfactant and X5: water) was developed, and the response surface methodology was used to study the effect of formulation components on physiochemical characteristics and penetration capacity of a catechin-loaded microemulsion, and to obtain an optimal microemulsion formulation. The results showed that the drug-loaded microemulsion formation and characteristics were related to many parameters of the components. The transdermal amounts in receiver cells and skin deposition amount remarkably increased about 4.1-111.6-fold and 0.6-7.6-fold respectively. The lag time was significantly shortened from 10h to 1.0-6.7h. The optimal formulation with 20% surfactant, 30% cosurfactant and 2.6% Catechin was subjected to stability and irritation tests. The results showed that the physicochemical characteristics and catechin level of the drug-loaded microemulsion did not show significant degradation after 3 months of storage at 25°C.The catechin-loaded microemulsion did not cause significant irritation compared to the water-treated group.


Asunto(s)
Catequina/administración & dosificación , Emulsiones/química , Absorción Cutánea , Piel/metabolismo , Administración Cutánea , Animales , Catequina/química , Catequina/farmacocinética , Fenómenos Químicos , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Interacciones Hidrofóbicas e Hidrofílicas , Ratas Sprague-Dawley , Piel/citología , Tensoactivos/química , Agua/química
18.
Int J Nanomedicine ; 13: 2789-2802, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29785106

RESUMEN

BACKGROUND: SN38 (7-ethyl-10-hydroxycamptothecin) is a camptothecin derivative acts against various tumors. However, SN38 is hydrolyzed in the physiological environment (pH 7.4), and this instability interferes with its potential therapeutic effect. Our objective was to investigate SN38-loaded liposomes to overcome the poor solubility of SN38 and its biodistribution, which further diminish its toxicity. MATERIALS AND METHODS: The sub-100 nm targeted liposomes was employed to deliver SN-38 and evaluate the characterization, release behaviors, cytotoxicity, in vivo pharmacokinetics and biochemical assay. RESULTS: The SN38-loaded targeted liposomes consisted of small (100.49 nm) spherical nanoparticles with negative charge (-37.93 mV) and high entrapment efficiency (92.47%). The release behavior of the SN38-loaded targeted liposomes was fitted with Higuchi kinetics (R2=0.9860). Free SN38 presented initial burst release. The IC50 for the SN38-loaded targeted liposomes (0.11 µM) was significantly lower than for the SN38 solution (0.37 µM) in the MCF7 cell line (P<0.01). Confocal laser scanning microscopy also confirmed highly efficient accumulation in the MCF7 cells. Pharmacokinetics demonstrated that the SN38-loaded targeted liposomes had a slightly increased half-life and mean residence time and decreased area under the concentration-time curve and maximum concentration. The results suggested that retention was achieved while the exposure of SN38 was significantly decreased. A noninvasive in vivo imaging system also showed that the targeted liposomes selectively targeted MCF7 tumors. In vivo toxicity data demonstrated that the decrease in platelets was significantly improved by SN38-loaded targeted liposomes, and diarrhea was not observed in BALB/c mice. CONCLUSION: In summary, SN38-loaded targeted liposomes could be a good candidate for application in human breast cancer.


Asunto(s)
Camptotecina/análogos & derivados , Liposomas/administración & dosificación , Nanopartículas/administración & dosificación , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/farmacocinética , Camptotecina/administración & dosificación , Camptotecina/efectos adversos , Camptotecina/farmacocinética , Liberación de Fármacos , Humanos , Irinotecán , Liposomas/química , Células MCF-7 , Masculino , Ratones Endogámicos BALB C , Imagen Molecular/métodos , Nanopartículas/química , Nanopartículas/toxicidad , Tamaño de la Partícula , Solubilidad , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Eur J Pharm Sci ; 122: 185-194, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29981405

RESUMEN

The UVA absorbers such as avobenzone are widely used for sunlight protection; however, they show a significant skin penetration. The aim of the present study was to formulate UVA absorbers into mesoporous silicas (MSs) for enhanced UVA protection with reduced percutaneous absorption. Two MSs prepared with different structure-directing agents (Pluronic P123 as single MS and combined Pluronic P123-Pluronic F68 as hybrid MS) were synthesized in this study. The hybrid MS exhibited higher specific surface area (853 m2/g) than the single MS (764 m2/g). The particle sizes of single MS and hybrid MS were about 1 and 1.5 µm, respectively. The adsorbed avobenzone had greatly decreased crystallinity compared with free avobenzone. The in vitro photoprotection determined by UVA/UVB ratio showed that the MS-loaded avobenzone in hydrogel endowed a synergistic effect on UVA protection compared to the free avobenzone. The skin absorption test using Franz diffusion cell indicated that the skin permeation of avobenzone and oxybenzone from MSs in semisolid preparations was one-third to one-half of those from free control. This effect was observed by using both pig skin and UVA-damaged nude mouse skin as the penetration barriers. Topical application of hybrid MS on nude mouse skin before UVA irradiation had prevented the increased transepidermal water loss (TEWL), furrow formation, keratinocyte apoptosis, and neutrophil infiltration. Our findings conclude that MSs containing avobenzone or oxybenzone effectively ameliorated UVA-induced skin disruption and reduced the possible toxicity elicited by percutaneous penetration.


Asunto(s)
Benzofenonas , Portadores de Fármacos , Hidrogeles , Propiofenonas , Dióxido de Silicio , Protectores Solares , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Benzofenonas/administración & dosificación , Benzofenonas/química , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Femenino , Hidrogeles/administración & dosificación , Hidrogeles/química , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , Ratones Desnudos , Poloxaleno/administración & dosificación , Poloxaleno/química , Poloxámero/administración & dosificación , Poloxámero/química , Porosidad , Propiofenonas/administración & dosificación , Propiofenonas/química , Dióxido de Silicio/administración & dosificación , Dióxido de Silicio/química , Piel/efectos de los fármacos , Piel/metabolismo , Piel/patología , Piel/efectos de la radiación , Absorción Cutánea/efectos de los fármacos , Protectores Solares/administración & dosificación , Protectores Solares/química , Porcinos , Rayos Ultravioleta
20.
BMJ Open ; 7(6): e014424, 2017 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-28667203

RESUMEN

OBJECTIVES: Coronary artery aneurysm (CAA) is usually an asymptomatic and rare disease. There are limited epidemiological data for CAA in Asian populations and in the rest of the world. DESIGN: A retrospective case control study. SETTING: A population based, database study from Taiwan's National Health Insurance Research Database, between 2005 and 2011. PARTICIPANTS: CAA patients identified using International Classification of Diseases, ninth revision, clinical modification (ICD-9-CM) code 414.11 with CAA examinations. OUTCOME MEASURES: The incidence rate and mortality rate of CAA were calculated. We also matched patients with non-CAA patients according to age, gender and index year at a 1:10 ratio to explore the risk factors for CAA using conditional logistic regression. RESULT: A total of 1397 CAA patients were identified between 2005 and 2011; 41.9% were paediatric patients and 58.1% were adults. The incidence rate and mortality rate of CAA in Taiwan were 0.87 and 0.05 per 105 person-years, respectively. The adjusted odds ratios (aOR) for coronary atherosclerosis, hypertension, dyslipidaemia and diabetes were 7.97, 2.09, 2.48 and 1.51, respectively. Of note, aortic dissection (aOR 6.76), aortic aneurysm (aOR 5.82) and systemic lupus erythematosus (aOR 4.09) were found to be significantly associated with CAA. CONCLUSION: In Taiwan, CAA patients were distributed across both paediatric and adult populations. Apart from cardiovascular risk factors, aortic diseases and systemic lupus erythematosus need to be investigated further in CAA patients.


Asunto(s)
Aneurisma Coronario/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Estudios de Casos y Controles , Niño , Comorbilidad , Aneurisma Coronario/etiología , Aneurisma Coronario/mortalidad , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo , Taiwán/epidemiología , Adulto Joven
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