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1.
J Synchrotron Radiat ; 31(Pt 1): 202-207, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37930256

RESUMEN

Near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy is a powerful tool for identifying chemical bonding states at synchrotron radiation facilities. Advances in new materials require researchers in both academia and industry to measure tens to hundreds of samples during the available beam time on a synchrotron beamline, which is typically allocated to users. Automated measurement methods, along with analysis software, have been developed for beamlines. Automated measurements facilitate high-throughput experiments and accumulate vast amounts of measured spectral data. The analysis software supports various functions for analyzing the experimental data; however, these analysis methods are complicated, and learning them can be time-consuming. To process large amounts of spectral data, a new analysis software, dedicated to NEXAFS spectroscopy, that is easy to use and can provide results in a short time is desired. Herein, the development of Beagle is described, software calculating molecular orientation from NEXAFS spectroscopy data that can report results in a short time comparable with that required to measure one sample at the beamline. It was designed to progress in a single sequence from data loading to the printing of the results with a `click of a button'. The functions of the software include recognizing the dataset, correcting the background, normalizing the plot, calculating the electron yield and determining the molecular orientation. The analysis results can be saved as {\tt{.txt}} files (spectral data), {\tt{.pdf}} files (graphic images) and Origin files (spectral data and graphic images).

2.
Pharm Res ; 41(5): 947-958, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38589647

RESUMEN

PURPOSE: We aim to present a refined thin-film model describing the drug particle dissolution considering radial diffusion in spherical boundary layer, and to demonstrate the ability of the model to describe the dissolution behavior of bulk drug powders. METHODS: The dissolution model introduced in this study was refined from a radial diffusion-based model previously published by our laboratory (So et al. in Pharm Res. 39:907-17, 2022). The refined model was created to simulate the dissolution of bulk powders, and to account for the evolution of particle size and diffusion layer thickness during dissolution. In vitro dissolution testing, using fractionated hydrochlorothiazide powders, was employed to assess the performance of the model. RESULTS: Overall, there was a good agreement between the experimental dissolution data and the predicted dissolution profiles using the proposed model across all size fractions of hydrochlorothiazide. The model over-predicted the dissolution rate when the particles became smaller. Notably, the classic Nernst-Brunner formalism led to an under-estimation of the dissolution rate. Additionally, calculation based on the equivalent particle size derived from the specific surface area substantially over-predicted the dissolution rate. CONCLUSION: The study demonstrated the potential of the radial diffusion-based model to describe dissolution of drug powders. In contrast, the classic Nernst-Brunner equation could under-estimate drug dissolution rate, largely due to the underlying assumption of translational diffusion. Moreover, the study indicated that not all surfaces on a drug particle contribute to dissolution. Therefore, relying on the experimentally-determined specific surface area for predicting drug dissolution is not advisable.


Asunto(s)
Liberación de Fármacos , Hidroclorotiazida , Tamaño de la Partícula , Polvos , Solubilidad , Polvos/química , Difusión , Hidroclorotiazida/química , Química Farmacéutica/métodos , Modelos Químicos , Simulación por Computador
3.
Molecules ; 27(4)2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35209181

RESUMEN

The solubility of glibenclamide was evaluated in DMSO, NMP, 1,4-dioxane, PEG 400, Transcutol® HP, water, and aqueous mixtures (T = 293.15~323.15 K). It was then recrystallized to solvate and compressed into tablets, of which 30-day stability and dissolution was studied. It had a higher solubility in 1,4-dioxane, DMSO, NMP (Xexp = 2.30 × 103, 3.08 × 104, 2.90 × 104) at 323.15 K, its mixture (Xexp = 1.93 × 103, 1.89 × 104, 1.58 × 104) at 298.15 K, and 1,4-dioxane (w) + water (1-w) mixture ratio of w = 0.8 (Xexp = 3.74 × 103) at 323.15 K. Modified Apelblat (RMSD ≤ 0.519) and CNIBS/R-K model (RMSD ≤ 0.358) suggested good comparability with the experimental solubility. The minimum value of ΔG° vs ΔH° at 0.70 < x2 < 0.80 suggested higher solubility at that molar concentration. Based on the solubility, it was recrystallized into the solvate, which was granulated and compressed into tablets. Among the studied solvates, the tablets of glibenclamide dioxane solvate had a higher initial (95.51%) and 30-day (93.74%) dissolution compared to glibenclamide reference (28.93%). There was no stability issue even after granulation, drying, or at pH 7.4. Thus, glibenclamide dioxane solvate could be an alternative form to improve the molecule's properties.


Asunto(s)
Liberación de Fármacos , Gliburida/química , Gliburida/farmacología , Termodinámica , Cromatografía Líquida de Alta Presión , Cristalización , Estabilidad de Medicamentos , Estructura Molecular , Solubilidad , Solventes/química , Análisis Espectral
4.
Molecules ; 26(2)2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33450987

RESUMEN

The solubility and dissolution thermodynamics of new c-Met inhibitor, ABN401, were determined in eleven solvents and Transcutol® HP-water mixture (TWM) from 298.15 to 318.15 K. The experimental solubilities were validated using five mathematical models, namely modified Apelblat, van't Hoff, Buchowski-Ksiazaczak λh, Yalkowsky, and Jouyban-Acree van't Hoff models. The experimental results were correlated and utilized further to investigate the feasibility of nanosuspension formation using liquid anti-solvent precipitation. Thermodynamic solubility of ABN401 increased significantly with the increase in temperature and maximum solubility was obtained with Transcutol® HP while low solubility in was obtained water. An activity coefficient study indicated that high molecular interaction was observed in ABN401-Transcutol® HP (THP). The solubility increased proportionately as the mole fraction of Transcutol® HP increased in TWM, which was also supported by a solvent effect study. The result suggested endothermic and entropy-driven dissolution. Based on the solubility, nanosuspension was designed with Transcutol® HP as solvent, and water as anti-solvent. The mean particle size of nanosuspension decreased to 43.05 nm when the mole fraction of ABN401 in THP, and mole fraction of ABN401 in TWM mixture were decreased to 0.04 and 0.1. The ultrasonicated nanosuspension appeared to give comparatively higher dissolution than micronized nanosuspension and provide a candidate formulation for in vivo purposes.


Asunto(s)
Nanopartículas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Humanos , Modelos Químicos , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas c-met/metabolismo , Solubilidad , Solventes/química , Termodinámica
5.
J Nanobiotechnology ; 18(1): 88, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32522274

RESUMEN

Nanocomposite hydrogels capable of undergoing manufacturing process have recently attracted attention in biomedical applications due to their desired mechanical properties and high functionality. 3D printing nanocomposite hydrogels of hyaluronic acid (HA)/nanodiamond (ND) revealed that the addition of ND with the low weight ratio of 0.02 wt% resulted in higher compressive force and gel breaking point, compared with HA only nanocomposites. These HA nanocomposite hydrogels loaded with surface functionalized ND allowed for the enforced compressive stress to be tuned in a pH-dependent manner. HA nanocomposite hydrogels with ND-OH at pH 8 showed an increase of 1.40-fold (0.02%: 236.18 kPa) and 1.37-fold (0.04%: 616.72 kPa) the compressive stress at the composition of 0.02 wt% and 0.04 wt, respectively, compared to those of ND-COOH (0.02%: 168.31 kPa, 0.04%: 449.59 kPa) at the same pH. Moreover, the compressive stress of HA/ND-OH (0.04 wt%) at pH 8 was mechanically enhanced 1.29-fold, compared to that of HA/ND-OH (0.04 wt%) at pH 7. These results indicate that the tunable buffering environment and interaction with the long chains of HA at the molecular level have a critical role in the dependency of the mechanical properties on pH. Due to the pH stability of the ND-OH nanophase, filament-based processing and layer-based deposition at microscale attained enforced mechanical properties of hydrogel. Fine surface tuning of the inorganic ND nanophase and controlled 3D printing leads to improved control over the pH-dependent mechanical properties of the nanocomposite hydrogels reported herein.


Asunto(s)
Ácido Hialurónico/química , Hidrogeles/química , Nanocompuestos/química , Nanodiamantes/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Impresión Tridimensional , Reología , Estrés Mecánico
6.
Chem Pharm Bull (Tokyo) ; 65(2): 166-177, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27904030

RESUMEN

Even though experimental designs are becoming popular especially for conventional dosage forms, limited studies have been performed to optimize formulations of orally disintegrating films (ODFs). This study aimed to evaluate sildenafil citrate-loaded ODFs for a controlled release with hydroxypropyl methylcellulose as a film-forming polymer. A factorial design was utilized for optimization with three control factors: ethanol ratio, plasticizer ratio, and the type of plasticizer. Tensile strength, disintegration time, water contact angle, and thickness were chosen as responses. For optimization, water contact angle, disintegration time, and thickness were minimized, while the tensile strength was maximized. Based on the conditions, optimal formulations were achieved for each type of plasticizer. Evaluation of desirability indicated that the response values were close to the target. When these optimal formulations were validated, the optimal solutions and target values were similar with small biases. The formulations were characterized using scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, surface pH, in vitro dissolution, and drug release simulation with a mathematical modeling. After the drug was homogenously dispersed throughout the film, the crystalline form of the drug provided strong hydrogen bonds between the drug and the film components. Moreover, it showed a controlled drug release profiles that were well matched with simulated results. This study suggests that the optimized films may present a better alternative to conventional tablets for the treatment of male erectile dysfunction.


Asunto(s)
Composición de Medicamentos/métodos , Liberación de Fármacos , Derivados de la Hipromelosa/administración & dosificación , Derivados de la Hipromelosa/química , Modelos Químicos , Citrato de Sildenafil/administración & dosificación , Citrato de Sildenafil/química , Administración Oral , Química Farmacéutica , Plastificantes , Solubilidad , Resistencia a la Tracción
7.
J Microencapsul ; 34(6): 545-559, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28805467

RESUMEN

Even though ß-lapachone is a novel drug with pharmacological activity, it has limitations including instability under light conditions. The main purpose of the study was to enhance the stability of ß-lapachone using the microencapsulation method. The Shirasu porous glass membrane was used to achieve uniform-sized microcapsules. The prepared microcapsules were evaluated to investigate how process parameters affect the encapsulation efficiency, photostability and particle size distribution. The experimental design was conducted to obtain optimal formulations. In addition, an operating space was drawn to identify the safer range of control factors. All control factors showed significant effects on the encapsulation efficiency and photostability. For example, when a large amount of polymers was used, encapsulation efficiency and photostability were improved. However, as the amount of polymers increased, large and polydisperse microcapsules were produced. The robust design method provided information to characterise significant factors, thereby allowing effective control of photostability and size of microcapsules.


Asunto(s)
Naftoquinonas/química , Tecnología Farmacéutica , Estabilidad de Medicamentos , Tamaño de la Partícula , Porosidad , Difracción de Rayos X
8.
Biol Pharm Bull ; 39(4): 524-31, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26804133

RESUMEN

The transforming growth factor (TGF)-ß-Smad signaling pathway regulates collagen biosynthesis in human dermal fibroblasts. We found that ß-lapachone stimulated type I collagen expression in human dermal fibroblasts. In this study, we evaluated whether the ß-lapachone-induced upregulation of collagen biosynthesis in human dermal fibroblasts is associated with the TGF-ß-Smad signaling pathway. In cultured human dermal fibroblasts, both Smad 2 and Smad 3 (Smad 2/3) were phosphorylated by ß-lapachone treatment in a concentration-dependent manner. SB431542, a specific inhibitor of TGF-ß receptor I kinase, inhibited the ß-lapachone-mediated Smad 2/3 phosphorylation and type I collagen expression, suggesting that ß-lapachone stimulates collagen production via the TGF-ß receptor I kinase-dependent pathway. ß-Lapachone did not increase TGF-ß1 synthesis in human dermal fibroblasts, suggesting that the molecular mechanism of ß-lapachone for the upregulation of collagen synthesis is due to the extracellular regulation of availability and activities of TGF-ß. This study provides new insights into the role of ß-lapachone in collagen synthesis in human dermal fibroblasts and suggests that ß-lapachone can be used as a pharmacological tool to study collagen homeostasis associated with TGF-ß-Smad signaling.


Asunto(s)
Colágeno Tipo I/biosíntesis , Fibroblastos/efectos de los fármacos , Naftoquinonas/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colágeno Tipo I/genética , Fibroblastos/metabolismo , Humanos , Fosforilación/efectos de los fármacos , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Piel/citología , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
9.
Chem Pharm Bull (Tokyo) ; 64(5): 381-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27150470

RESUMEN

Even though ß-lapachone is a promising compound with antitumor, antiinflammatory, antineoplastic, and wound-healing effects, there are still issues concerning its chemical stability and degradation mechanisms. The objective of this study was to obtain degradation profiles of ß-lapachone and evaluate its chemical stability under various stress conditions. Moreover, the correlation between stability and efficacy was evaluated. The degradation study of ß-lapachone was performed using heat, acid, base, oxidation, and light conditions. Kinetics and degradation profiles were investigated with HPLC and LC-MS. The stability indicated in the LC method was validated according to the International Conference on Harmonization guidelines. Human dermal fibroblast (HDF) cells were cultured with the standard and its degraded samples in the cellular activity and cytotoxicity test. ß-Lapachone was relatively unstable upon exposure to light, and its photodegradation was accelerated with high relative humidity. Three degradants were identified, and their degradation followed zero-order kinetics. It was shown to degrade to phthalic acid under oxidative conditions, and the degradation kinetics were dependent on the concentration of hydrogen peroxide. Two degradation products were identified upon exposure to basic conditions, which followed first-order kinetics. ß-Lapachone was relatively stable under acidic and thermal conditions. It increased the synthesis of collagen compared with the control. However, as the contents decreased, the synthesis of collagen also decreased in the photodegraded samples. ß-Lapachone did not exert cytotoxic effects at the effective concentration in the cytotoxicity test. Therefore, in order to ensure efficacy and safety, the chemical stability of ß-lapachone needs to be controlled carefully while considering instability mechanisms.


Asunto(s)
Naftoquinonas/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Estabilidad de Medicamentos , Humanos , Cinética , Estructura Molecular , Naftoquinonas/síntesis química , Naftoquinonas/toxicidad
10.
Pharm Res ; 32(3): 929-40, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25231009

RESUMEN

PURPOSE: To evaluate the feasibility of iontophoresis and the combination effects with chemical enhancers on in vivo hypocalcemic effect of transbuccally delivered salmon calcitonin (sCT). METHODS: N-acetyl-L-cysteine (NAC), sodium deoxyglycocholate (SDGC), and ethanol were used as chemical enhancers; and 0.5 mA/cm(2) fixed electric current was employed as a physical enhancer. sCT hydrogel was applied to rabbit buccal mucosa, and blood samples were obtained via the central auricular artery. Blood calcium level was measured by calcium kit and the conformational changes of buccal mucosa were investigated with FT-IR spectroscopy. Hematoxylin/eosin staining was used for the histological evaluation of buccal mucosa. RESULTS: Iontophoresis groups except iontophoresis-NAC group showed significant hypocalcemic effect compared to negative control, in particular iontophoresis-SDGC combination group showed fast onset of action as well as sustained hypocalcemic effect (p < 0.05). FT-IR result demonstrated the reduction of buccal barrier function, and the histological study showed a decrease in buccal thickness as well as minor damage to the dermal-epidermal junctions in the enhancing method groups; however, the damaged tissues virtually recovered within 24 h after the removal of electrodes. CONCLUSIONS: Iontophoresis and combination with SDGC were found to be safe and potential strategies for transbuccal peptide delivery in vivo.


Asunto(s)
Calcitonina/administración & dosificación , Excipientes/administración & dosificación , Iontoforesis , Mucosa Bucal/efectos de los fármacos , Absorción por la Mucosa Oral/efectos de los fármacos , Acetilcisteína/administración & dosificación , Administración Bucal , Animales , Biomarcadores/sangre , Calcitonina/química , Calcitonina/farmacocinética , Calcitonina/toxicidad , Calcio/sangre , Química Farmacéutica , Regulación hacia Abajo , Etanol/administración & dosificación , Excipientes/química , Excipientes/toxicidad , Estudios de Factibilidad , Hidrogeles , Inyecciones Intravenosas , Masculino , Mucosa Bucal/metabolismo , Mucosa Bucal/patología , Permeabilidad , Conejos , Espectroscopía Infrarroja por Transformada de Fourier , Tecnología Farmacéutica/métodos
11.
Drug Dev Ind Pharm ; 41(2): 300-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24502269

RESUMEN

Correlation of thermodynamic and secondary structural stability of proteins at various buffer pHs was investigated using differential scanning calorimetry (DSC), dynamic light scattering (DLS) and attenuated total reflection Fourier-transform infrared spectroscopy (ATR FT-IR). Recombinant human epithelial growth factor (rhEGF) was selected as a model protein at various pHs and in different buffers, including phosphate, histidine, citrate, HEPES and Tris. Particle size and zeta potential of rhEGF at each selected pH of buffer were observed by DLS. Four factors were used to characterize the biophysical stability of rhEGF in solution: temperature at maximum heat flux (Tm), intermolecular ß-sheet contents, zeta size and zeta potential. It was possible to predict the apparent isoelectric point (pI) of rhEGF as 4.43 by plotting pH against zeta potential. When the pH of the rhEGF solution increased or decreased from pI, the absolute zeta potential increased indicating a reduced possibility of protein aggregation, since Tm increased and ß-sheet contents decreased. The contents of induced intermolecular ß-sheet in Tris and HEPES buffers were the lowest. Thermodynamic stability of rhEGF markedly increased when pH is higher than 6.2 in histidine buffer where Tm of first transition was all above 70 °C. Moreover, rhEGF in Tris buffer was more thermodynamically stable than in HEPES with higher zeta potential. Tris buffer at pH 7.2 was concluded to be the most favorable.


Asunto(s)
Factor de Crecimiento Epidérmico/química , Fenómenos Biofísicos , Tampones (Química) , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Humanos , Concentración de Iones de Hidrógeno , Luz , Modelos Químicos , Tamaño de la Partícula , Agregado de Proteínas , Estabilidad Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Dispersión de Radiación , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
12.
Eur Arch Psychiatry Clin Neurosci ; 264(1): 71-81, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24068320

RESUMEN

Circadian rhythm disturbance is highly prevalent in attention deficit hyperactivity disorder (ADHD). Recently, the association between the CLOCK gene and ADHD has been demonstrated in clinical samples, and the CLOCK gene's role was thought to be mediated by rhythm dysregulation. Meanwhile, ADHD has been suggested as the extreme end of a continuously distributed trait that can be found in the general population. Therefore, we examined two possibilities: (1) an ADHD-related continuous trait may be associated with the CLOCK gene, and (2) this association may be mediated by the degree of individuals' evening preference. To explore these possibilities, we performed a quantitative trait locus association study with a sample of 1,289 healthy adults. The Wender Utah Rating Scale (WURS) and the Composite Scale of Morningness (CSM) were utilized to measure the quantitative traits. Quantitative association analysis was performed using PLINK software. We found that rs1801260 (=T3111C) was associated with WURS scores in both allele-wise (p = 0.018) and haplotype-wise analyses (range of p values: 0.0155-0.0171) in male participants only. After controlling for the CSM total score as a covariate, the strength of the association did not change at all, suggesting that the association was not mediated by evening preference. Despite the very weak association signal, our results provide evidence that the CLOCK gene's association with ADHD in clinical samples may be generalizable to traits measured in the normal population. However, as our results failed to show a mediating role of evening preference, ongoing efforts are needed to identify the mechanisms by which the CLOCK gene determines ADHD-related traits.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/genética , Proteínas CLOCK/genética , Ritmo Circadiano/genética , Escalas de Valoración Psiquiátrica , Adolescente , Adulto , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Estadística como Asunto , Adulto Joven
13.
Biol Pharm Bull ; 37(5): 808-16, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24790003

RESUMEN

The protein size, electrical interaction, and conformational stability of etanercept (marketed as Enbrel®) were examined by thermodynamic and light scattering methods with changing pH and buffer concentration. As pH of etanercept increased from pH 6.6 to 8.6, electrical repulsion in the solution increased, inducing a decrease in protein size. However, the size changed less in high buffer concentration and irreversible aggregation issues were not observed; in contrast, aggregates of about 1000 nm were observed in low buffer concentration at the pH range. Three significant unfolding transitions (Tm) were observed by differential scanning calorimetry (DSC). Unlikely to Tm1, Tm2 and Tm3 were increased as the pH increased. Higher Tm at high buffer concentration was observed, indicating increased conformational stability. The apparent activation energy of unfolding was further investigated since continuous increase of Tm2 and Tm3 was not sufficient to determine optimal conditions. A higher energy barrier was calculated at Tm2 than at Tm3. In addition, the energy barriers were the highest at pH from 7.4 to 7.8 where higher Tm1 was also observed. Therefore, the conformational stability of protein solution significantly changed with pH dependent steric repulsion of neighboring protein molecules. An optimized pH range was obtained that satisfied the stability of all three domains. Electrostatic circumstances and structural interactions resulted in irreversible aggregation at low buffer concentrations and were suppressed by increasing the concentration. Therefore, increased buffer concentration is recommended during protein formulation development, even in the earlier stages of investigation, to avoid protein instability issues.


Asunto(s)
Estabilidad de Medicamentos , Inmunoglobulina G/química , Receptores del Factor de Necrosis Tumoral/química , Tampones (Química) , Rastreo Diferencial de Calorimetría , Etanercept , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Agregado de Proteínas , Conformación Proteica , Propiedades de Superficie , Termodinámica , Temperatura de Transición
14.
Drug Dev Ind Pharm ; 40(3): 308-17, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23786206

RESUMEN

Electronic tongue systems have been developed for taste measurement of bitter drug substances in accurate taste comparison to development palatable oral formulations. This study was to evaluate the taste masking effect of conventional pharmaceutical sweeteners such as neohesperidin dihydrochalcone, sucrose, sucralose and aspartame. The model drugs were acetaminophen, ibuprofen, tramadol hydrochloride, and sildenafil citrate (all at 20 mM). The degree of bitterness was measured by a multichannel taste sensor system (an electronic tongue). The data was collected by seven sensors and analyzed by a statistical method of principal components analysis (PCA). The effect of taste masking excipient was dependent on the type of model drug. Changing the concentration of taste masking excipients affected the sensitivity of taste masking effect according to the type of drug. As the excipient concentration increased, the effect of taste masking increased. Moreover, most of the sensors showed a concentration-dependent pattern of the taste-masking agents as higher concentration provided higher selectivity. This might indicate that the sensors can detect small concentration changes of a chemical in solution. These results suggest that the taste masking could be evaluated based on the data of the electronic tongue system and that the formulation development process could be performed in a more efficient way.


Asunto(s)
Equipos y Suministros Eléctricos , Excipientes/química , Edulcorantes/química , Gusto , Química Farmacéutica/métodos , Preparaciones Farmacéuticas/química , Análisis de Componente Principal , Lengua
15.
Int Clin Psychopharmacol ; 39(3): 187-194, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38261424

RESUMEN

It was reported that patients who contracted COVID-19 while taking clozapine exhibited a distinct hematological response. However, the absence of control groups made it difficult to attribute it to clozapine. The changes in absolute neutrophil counts (ANCs) during the 4 weeks after COVID-19 infection were compared between the two groups of patients with severe mental illnesses (SMIs) (49 patients using clozapine and 54 using other antipsychotics) using generalized additive modeling. Although the pattern of a transient drop in ANC followed by gradual recovery could be demonstrated in both groups, it was more pronounced in the clozapine group ( P  = 0.00025). Nevertheless, overall ANC remained at a higher level in the clozapine group. The results suggested potential interaction between clozapine and COVID-19 at the level of hematological dynamics. However, it did not necessarily indicate that such interaction is inevitably harmful or dangerous. It was more of a concern that some patients using other antipsychotics exhibited decreased ANC, which did not easily recover. Traditionally, clinicians have been concerned about the worsening of hematological side effects in clozapine patients after COVID-19 infection. However, the obtained result highlighted the necessity of hematological monitoring in patients using any type of antipsychotics for SMIs.


Asunto(s)
Antipsicóticos , COVID-19 , Clozapina , Humanos , Antipsicóticos/efectos adversos , Clozapina/efectos adversos , Neutrófilos , Recuento de Leucocitos
16.
Psychiatry Investig ; 21(4): 403-414, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38695048

RESUMEN

OBJECTIVE: Auditory verbal hallucination (AVH) is a prominent symptom of schizophrenia causing profound distress. The influence of AVHs on insight appears to be intricate and contingent on other accompanying symptoms. This study investigated the relationship and possible mediators between AVHs and the degree of insight. METHODS: One hundred patients with schizophrenia participated in the study. Scales were used to evaluate the hallucinatory experience, the level of insight and other psychopathology. Complex relationships between variables were envisaged as a path model, whose initial structure was constructed via Gaussian Graphical Model. The validity of the final model was verified by Structural Equation Modeling. Separate analyses were performed for self-reported and clinician-rated data to enhance the model's robustness. RESULTS: The greater the severity of the physical aspects of AVHs, the lower the level of insight observed. Conversely, higher emotional distress was associated with increased insight. These relationships were only evident in the self-reported results and were not reflected in the clinician-rated results. The path model suggested that the Positive and Negative Syndrome Scale (PANSS) anxiety/depression factor was an important mediator that linked the found association. Notably, the PANSS negative symptom had the opposite effect on the PANSS anxiety/depression factor and insight, making it difficult to define its overall effect. CONCLUSION: The findings of this study provided one possible route for the positive influence of AVH experience in gaining insight. The mediating role of anxiety/depression modified by negative symptoms emerged as a valuable concept for clarifying this intricate relationship.

17.
Dig Dis Sci ; 58(5): 1226-34, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23192646

RESUMEN

BACKGROUND: Co-administration of a reduction inhibitor and a colon-specific prodrug of a glucocorticoid susceptible to colonic reductive metabolism is suggested as a strategy to circumvent the therapeutic loss of the glucocorticoid delivered to and acting locally at the large intestine. AIMS: We examined whether the strategy was feasible as a pharmacotherapy for treatment of inflammatory bowel disease. METHODS: Glycyrrhizin (GCZ), a reduction inhibitor, was tested for its inhibition of the colonic metabolism of methylprednisolone (MP). Therapeutic activity against TNBS-induced rat colitis and adrenal suppression were compared after oral administration of methylprednisolone 21-sulfate sodium (MPS), a colon-specific prodrug of MP, or MPS/GCZ to colitic rats. RESULTS: Upon incubation of MP with the cecal contents, MP disappeared, and this was delayed by addition of GCZ. In addition, more MP produced from MPS in the cecal contents accumulated in the presence of GCZ. Consistent with these results, upon oral administration of MPS/GCZ, MPS or MP, MP was detected at a greater level in the large intestine for MPS/GCZ. MPS/GCZ ameliorated TNBS-induced colitis of rats, and this therapeutic effect was superior to that of MPS and MP. Moreover, MPS/GCZ decreased the plasma levels of corticosterone and ACTH to a greater extent than MPS, but less than MP. CONCLUSIONS: Co-administration of GCZ, a reduction inhibitor, may be a plausible strategy to reduce the therapeutic loss of MP produced from MPS in the large intestine, thus improving the therapeutic property of the prodrug against inflammatory bowel disease.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis/tratamiento farmacológico , Ácido Glicirrínico/uso terapéutico , Metilprednisolona/uso terapéutico , Glándulas Suprarrenales/efectos de los fármacos , Animales , Antiinflamatorios/metabolismo , Colitis/metabolismo , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Masculino , Metilprednisolona/metabolismo , Profármacos/uso terapéutico , Ratas , Ratas Sprague-Dawley
18.
J Microencapsul ; 30(1): 1-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23137194

RESUMEN

A robust experimental design method was developed using a response surface methodology and models to facilitate the development process of retinol solid lipid nanoparticles (SLNs). The SLNs were evaluated to determine how different parameters including lipid and surfactant affect size and encapsulation efficiency. This was conducted using factorial analysis and a robust design (RD) method was used to achieve optimal formulations. Two models were developed based on the RD principle and both mean and variance of the response characteristics were estimated functionally using the least squares method. They proved useful in formulation studies aiming to develop optimum by allowing a systematic and reliable design method. A model for maximizing the overall desirability represented by the geometric mean of all objectives was found to provide a better solution. The newly designed method provides useful information to characterize significant factors and obtain optimum formulations, thereby allowing a systematic and reliable design method.


Asunto(s)
Lípidos/química , Nanopartículas , Vitamina A/química , Análisis de los Mínimos Cuadrados , Tamaño de la Partícula
19.
Int J Biol Macromol ; 232: 123439, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36716845

RESUMEN

The multi-dose vial (MDV) is widely used for most biopharmaceuticals that are repackaged in plastic syringes before use. However, subvisible particle formation with the use of plastic syringes containing silicone oil (SO syringes) for handling therapeutic proteins can be problematic. This study aimed to evaluate the extent of and trends in microparticle (>1 µm) formation and accumulation in repackaged syringes from MDVs containing human immunoglobulin (IgG) and lipid nanoparticles (LNPs). Light obscuration (LO) and flow imaging (FI) were used to analyze the microparticles. The number of microparticles observed with the use SO syringes was greater than that with SO-free syringes, and the number of microparticles continuously increased as did the number of times of repackaging in syringes for both drugs. However, a large variation was observed across different brands of SO syringes. In contrast, using a different technique of drug withdrawal from the vial significantly reduced the number of microparticles. Furthermore, the use of filter-integrated needles or the inclusion of stabilizers such as acetyl-arginine and Tween 20 into the formulation also helped reduce particle formation.


Asunto(s)
Inmunoglobulinas , Jeringas , Humanos , Bevacizumab , Plásticos
20.
Pharmaceutics ; 15(12)2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38140061

RESUMEN

MT-102 is a new anti-inflammatory agent derived from Juglans mandshurica and Isatis indigotica. Its therapeutic potential is hindered by low aqueous solubility, impacting its in vivo efficacy. Therefore, this study aimed to develop a self-microemulsifying drug delivery system (SMEDDS) for MT-102 to enhance its oral efficacy in treating ulcerative colitis. Solubility assessment in different oils, surfactants, and cosurfactants led to a SMEDDS formulation of MT-102 using Capmul MCM, Tween 80, and propylene glycol. Based on a pseudoternary phase diagram, the optimal SMEDDS composition was selected, which consisted of 15% Capmul MCM, 42.5% Tween 80, and 42.5% propylene glycol. The resulting optimized SMEDDS (SMEDDS-F1) exhibited a narrow size distribution (177.5 ± 2.80 nm) and high indirubin content (275 ± 5.58 µg/g, a biomarker). Across an acidic to neutral pH range, SMEDDS-F1 showed rapid and extensive indirubin release, with dissolution rates approximately 15-fold higher than pure MT-102. Furthermore, oral administration of SMEDDS-F1 effectively mitigated inflammatory progression and symptoms in a mouse model of ulcerative colitis, whereas pure MT-102 was ineffective. SMEDDS-F1 minimized body weight loss (less than 5%) without any significant change in colon length and the morphology of colonic tissues, compared to those of the healthy control group. In addition, oral administration of SMEDDS-F1 significantly inhibited the secretion of pro-inflammatory cytokines such as IL-6 and TNF-α. In conclusion, the SMEDDS-F1 formulation employing Capmul MCM, Tween 80, and propylene glycol (15:42.5:42.5, w/w) enhances the solubility and therapeutic efficacy of MT-102.

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