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1.
Cogn Emot ; : 1-16, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837896

RESUMEN

Previous studies have found that people with high negative emotional granularity(NEG) tend to have better health levels. It is generally believed that this is due to the selection and application of explicit emotion regulation strategies that affect mental health. However, no research has yet examined a more fundamental process, the role of affect labelling, an implicit emotion regulation strategy. This study focuses on the aforementioned issues and uses the experience sampling method to categorise participants into groups with high and low NEG. Using an affect labelling paradigm with ERP(event-related potential) technology, the study measures the effects of affect labelling in participants. Furthermore, it assesses the mental health levels of the participants through questionnaires to explore whether the affect labelling effect serves as a mediator between NEG and mental health. The results show that: (1) The high-NEG group exhibited significantly lower LPP wave amplitudes under affect labelling compared to under non-affect labelling, whereas the low-NEG group did not show significant differences. The results indicate that only the high-NEG group can produce the affect labelling effect. (2) The affect labelling effect mediates the relationship between NEG and mental health, meaning that NEG predicts mental health through the affect labelling effect.

2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(3): 708-716, 2024 May 20.
Artículo en Zh | MEDLINE | ID: mdl-38948268

RESUMEN

Objective: To explore the relationship between baseline clinical characteristics and hematological parameters of patients undergoing radical resection for pancreatic ductal adenocarcinoma (PDAC) and their prognosis, and to provide references for stratifying the patients' clinical risks. Methods: We retrospectively collected clinical data from 445 patients who underwent radical surgical treatment for PDAC at West China Hospital, Sichuan University between January 2010 and February 2019. Then, we conducted retrospective clinical analysis with the collected data. Data on patients' basic clinical characteristics, routine blood test results, and tumor indicators were collected to explore their effects on the postoperative overall survival (OS) of PDAC patients. Cox proportional hazards regression was used to identify factors affecting OS. Statistical analysis was performed using the SPSS 23.0 software package. Results: The postoperative median overall survival (mOS) was 17.0 months (95% CI: 15.0-19.0). The 1, 2, 3, 4, and 5-year survival rates of the patients included in the study were 60.6%, 33.4%, 19.1%, 12.7%, and 9.6%, respectively. The multivariate Cox proportional hazards model analysis demonstrated that a number of factors independently affect postoperative survival in PDAC patients. These factors include tumor location (hazards ratio [HR]=1.574, 95% CI: 1.233-2.011), degree of tumor cell differentiation (HR=0.687, 95% CI: 0.542-0.870), presence of neural invasion (HR=0.686, 95% CI: 0.538-0.876), TNM staging (HR=1.572, 95% CI: 1.252-1.974), postoperative adjuvant therapy (HR=1.799, 95% CI: 1.390-2.328), preoperative drinking history (HR=0.744, 95% CI: 0.588-0.943), and high serum CA199 levels prior to the surgery (HR=0.742, 95% CI: 0.563-0.977). Conclusion: In PDAC patients, having tumors located in the head of the pancreas, moderate and high degrees of differentiated, being free from local neurovascular invasion, being in TNM stage Ⅰ, undergoing postoperative adjuvant therapy, no history of alcohol consumption prior to the surgery, and preoperative serum CA199 being less than or equal to 37 U/mL are significantly associated with a better prognosis.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/patología , Estudios Retrospectivos , Pronóstico , Masculino , Femenino , Carcinoma Ductal Pancreático/cirugía , Carcinoma Ductal Pancreático/sangre , Tasa de Supervivencia , Modelos de Riesgos Proporcionales , Persona de Mediana Edad , China/epidemiología , Anciano
3.
J Cardiovasc Magn Reson ; 25(1): 37, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349765

RESUMEN

BACKGROUND: There is a paucity of quantitative measurements of cardiac tumors and myocardium using parametric mapping techniques. This study aims to explore quantitative characteristics and diagnostic performance of native T1, T2, and extracellular volume (ECV) values of cardiac tumors and left ventricular (LV) myocardium. METHODS: Patients with suspected cardiac tumors who underwent cardiovascular magnetic resonance (CMR) between November 2013 and March 2021 were prospectively enrolled. The diagnoses of primary benign or malignant tumors were based on pathologic findings if available, comprehensive medical history evaluations, imaging, and long-term follow-up data. Patients with pseudo-tumors, cardiac metastasis, primary cardiac diseases, and prior radiotherapy or chemotherapy were excluded. Multiparametric mapping values were measured on both cardiac tumors and the LV myocardium. Statistical analyses were performed using independent-samples t-test, receiver operating characteristic, and Bland-Altman analyses. RESULTS: A total of 80 patients diagnosed with benign (n = 54), or primary malignant cardiac tumors (n = 26), and 50 age and sex-matched healthy volunteers were included. Intergroup differences in the T1 and T2 values of cardiac tumors were not significant, however, patients with primary malignant cardiac tumors showed significantly higher mean myocardial T1 values (1360 ± 61.4 ms) compared with patients with benign tumors (1259.7 ± 46.2 ms), and normal controls (1206 ± 44.0 ms, all P < 0.05) at 3 T. Patients with primary malignant cardiac tumors also showed significantly higher mean ECV (34.6 ± 5.2%) compared with patients with benign (30.0 ± 2.5%) tumors, and normal controls (27.3 ± 3.0%, all P < 0.05). For the differentiation between primary malignant and benign cardiac tumors, the mean myocardial native T1 value showed the highest efficacy (AUC: 0.919, cutoff value: 1300 ms) compared with mean ECV (AUC: 0.817) and T2 (AUC: 0.619) values. CONCLUSION: Native T1 and T2 of cardiac tumors showed high heterogeneity, while myocardial native T1 values in primary malignant cardiac tumors were elevated compared to patients with benign cardiac tumors, which may serve as a new imaging marker for primary malignant cardiac tumors.


Asunto(s)
Neoplasias Cardíacas , Imagen por Resonancia Cinemagnética , Humanos , Estudios de Casos y Controles , Valor Predictivo de las Pruebas , Miocardio/patología , Imagen por Resonancia Magnética , Neoplasias Cardíacas/diagnóstico por imagen , Medios de Contraste
4.
J Nanobiotechnology ; 21(1): 325, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684605

RESUMEN

Bacterial infection has been a major threat to worldwide human health, in particular with the ever-increasing level of antimicrobial resistance. Given the complex microenvironment of bacterial infections, conventional use of antibiotics typically renders a low efficacy in infection control, thus calling for novel strategies for effective antibacterial therapies. As an excellent candidate for antibiotics delivery, mesoporous silica nanoparticles (MSNs) demonstrate unique physicochemical advantages in antibacterial therapies. Beyond the delivery capability, extensive efforts have been devoted in engineering MSNs to be bioactive to further synergize the therapeutic effect in infection control. In this review, we critically reviewed the essential properties of MSNs that benefit their antibacterial application, followed by a themed summary of strategies in manipulating MSNs into bioactive nanoplatforms for enhanced antibacterial therapies. The chemically functionalized platform, photo-synergized platform, physical antibacterial platform and targeting-directed platform are introduced in details, where the clinical translation challenges of these MSNs-based antibacterial nanoplatforms are briefly discussed afterwards. This review provides critical information of the emerging trend in turning bioinert MSNs into bioactive antibacterial agents, paving the way to inspire and translate novel MSNs-based nanotherapies in combating bacterial infection diseases.


Asunto(s)
Antibacterianos , Nanopartículas , Humanos , Antibacterianos/farmacología , Dióxido de Silicio
5.
Molecules ; 28(2)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36677650

RESUMEN

To improve the sustained release and long-term antibacterial activity of Chimonanthus nitens Oliv. essential oil (CEO), novel sponge-liked nanoporous silica particles (SNP) were synthesized via the soft template method, which was employed as a biocompatible carrier to prepare spong-liked nanoporous silica particles loading with CEO (CEO-SNP) through physical adsorption. The structure and properties of the samples were characterized via N2 adsorption/desorption measurements, thermogravimetry (TGA), Fourier transform infrared, SEM and TEM. The result showed that the SNP exhibited an excellent loading capability of CEO up to 76.3%. The thermal stability and release behavior of the CEO were significantly improved via the physical adsorption of the SNP materials. The release profile of CEO was in accordance with the first-order kinetic model, which meant that the release mechanism was drug Fick's diffusion. The antibacterial evaluation results demonstrated that the CEO-SNP exhibited strong antibacterial activity against S. aureus, E. coli and P. aeruginosa. The antibacterial results have shown that the CEO-SNP could destroy the cell structure of bacteria, and result in the generation of oxidative stress and the release of nucleic acid. After storage of 30 d at 25 °C, the CEO-SNP still had the stronger antibacterial activity towards S. aureus, E. coli and P. aeruginosa in comparison with CEO. Therefore, the sponge-like silica nanoporous particles seemed to be a promising carrier for long-term stability and antibacterial delivery of CEO.


Asunto(s)
Nanoporos , Aceites Volátiles , Aceites Volátiles/farmacología , Aceites Volátiles/química , Dióxido de Silicio/química , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química
6.
Pharmacol Res ; 179: 106189, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35331865

RESUMEN

Recently, comparative studies have rapidly increased with the closer correlation between microbiota and neurological diseases. However, most insights about the association between microbiota and neurological diseases still focus on the gut-brain axis and ignore that nasal microbiota could form a complex and essential link with the nervous system via the nose-to-brain pathway, suggesting the role in modulating the immune system, metabolic system, and nervous system development, which influence the physiopathology of neurological diseases. Due to the complex interactions between nasal microbiota and the brain, the nasal microbiota may have a particular pathogenic effect and therapeutic potential on neurological diseases. Therefore, this review aims to deeply analyze the dual effects of nasal microbiota on neurological diseases, focusing on pathogenic and therapeutic effects to provide a new perspective for preventing and treating neurological diseases by altering nasal microbiota. This review concludes the bidirectional effects of nasal microbiota on neurological diseases, including the pathogenicity and potential treatment on Alzheimer's disease, Parkinson's disease, Multiple sclerosis, and Stroke. Furthermore, modern medical technology combined with artificial intelligence, including implantable sensors, modeling software, and nanofluid techniques, may further study the complex effects between nasal microbiota and the brain, thereby providing new options for treating neurological diseases.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Enfermedades del Sistema Nervioso , Inteligencia Artificial , Encéfalo/metabolismo , Microbioma Gastrointestinal/fisiología , Humanos , Enfermedades del Sistema Nervioso/metabolismo , Factores de Riesgo
7.
Drug Dev Ind Pharm ; 47(11): 1700-1712, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35287534

RESUMEN

Nanocrystal technology is a new way to increase the solubility and bioavailability of poorly soluble drugs. As an intermediate preparation technology, nanocrystals are widely used in drug delivery for oral, venous, percutneous and inhalation administration, which exhibits a broad application prospect. By referring to the domestic anforeign literatures, this paper mainly reviews the preparation methods of nanocrystals for poorly soluble natural products and its application in the mucosal delivery for skin, eye, oral cavity and nasal cavity. This can provide the reference for the research and development of nanocrystal technology in natural product preparations.


Asunto(s)
Nanopartículas , Disponibilidad Biológica , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Preparaciones Farmacéuticas/química , Solubilidad
8.
Molecules ; 26(15)2021 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-34361634

RESUMEN

Prolonging in vivo circulation has proved to be an efficient route for enhancing the therapeutic effect of rapidly metabolized drugs. In this study, we aimed to construct a nanocrystal-loaded micelles delivery system to enhance the blood circulation of docetaxel (DOC). We employed high-pressure homogenization to prepare docetaxel nanocrystals (DOC(Nc)), and then produced docetaxel nanocrystal-loaded micelles (DOC(Nc)@mPEG-PLA) by a thin-film hydration method. The particle sizes of optimized DOC(Nc), docetaxel micelles (DOC@mPEG-PLA), and DOC(Nc)@mPEG-PLA were 168.4, 36.3, and 72.5 nm, respectively. The crystallinity of docetaxel was decreased after transforming it into nanocrystals, and the crystalline state of docetaxel in micelles was amorphous. The constructed DOC(Nc)@mPEG-PLA showed good stability as its particle size showed no significant change in 7 days. Despite their rapid dissolution, docetaxel nanocrystals exhibited higher bioavailability. The micelles prolonged the retention time of docetaxel in the circulation system of rats, and DOC(Nc)@mPEG-PLA exhibited the highest retention time and bioavailability. These results reveal that constructing nanocrystal-loaded micelles may be a promising way to enhance the in vivo circulation and bioavailability of rapidly metabolized drugs such as docetaxel.


Asunto(s)
Antineoplásicos/farmacocinética , Docetaxel/farmacocinética , Portadores de Fármacos/farmacocinética , Nanopartículas/administración & dosificación , Animales , Antineoplásicos/administración & dosificación , Docetaxel/administración & dosificación , Masculino , Micelas , Ratas , Ratas Sprague-Dawley
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 264-266, 2020 Mar.
Artículo en Zh | MEDLINE | ID: mdl-32220199

RESUMEN

A 53-year-old woman was found "an occupant in the left ciliary body" two years ago and underwent the surgery of "left eye ball removal". Pathological results confirmed the diagnosis of malignant melanoma. The patient was admitted to our hospital again due to newly found heart murmur. With the combination of cardiac magnetic resonance (CMR) imaging characteristics, including high signals on T1-weighted and fat-suppressed T1-weighted images, the high signal on T2-weighted images, uneven first-pass perfusion and late gadolinium enhancement (LGE), as well as PET signal characteristics, the diagnosis of malignant melanoma cardiac metastasis was made. This case suggests that multimodality CMR, including T1-weighted, T2-weighted, first-pass perfusion, late gadolinium enhancement, and cine imaging, can be used to monitor and detect cardiac metastasis of melanoma in a relatively early stage. Therefore, we recommend a routine echocardiography screening for patients diagnosed with melanoma. In addition, CMR examinations and PET/CT may help early detection and timely intervention of melanoma cardiac metastasis, as for their good specificity in detecting, this disease in clinical practice.


Asunto(s)
Neoplasias del Ojo , Neoplasias Cardíacas , Melanoma , Medios de Contraste , Neoplasias del Ojo/diagnóstico por imagen , Neoplasias del Ojo/patología , Neoplasias del Ojo/cirugía , Femenino , Gadolinio , Neoplasias Cardíacas/diagnóstico por imagen , Neoplasias Cardíacas/secundario , Humanos , Melanoma/diagnóstico por imagen , Melanoma/secundario , Persona de Mediana Edad , Miocardio , Tomografía Computarizada por Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas
10.
Phytother Res ; 32(3): 426-435, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29193364

RESUMEN

Efficient transcytosis across the blood-brain-barrier is an important strategy for accessing drug targets within the central nervous system. Ligusticum chuanxiong Hort. was used as a messenger drug to increase the distribution of drugs in brain tissue in Traditional Chinese Medicine. The present study investigates the transport of echinacoside (ECH) through MDCK-MDR1 cell and the effects of ligustilide (LIG), senkyunolide A (SENA) and senkyunolide I (SENI) in chuanxiong on its transport. The results indicated that the absorption of ECH was relatively poor in MDCK-MDR1cells, and was concentration dependent and not saturable. The P-glycoprotein inhibitor verapamil could significantly increase the transport of ECH. It indicated that the transport mechanism might be passive diffusion as the dominating process with the active transportation mediated mechanism involved. The increased apparent permeability of ECH in A â†’ B direction by ethylenediaminetetraacetic acid-Na2 suggested that ECH was absorbed via the paracellular route. The transport of ECH in A â†’ B direction significantly increased when co-administrated with increasing concentrations of LIG, SENI and SENA. Western blot analysis and a decrease in transepithelial electrical resistance during the permeation experiment indicated that LIG, SENI and SENA had enhanced the transport of ECH in the BBB models attribute to down-regulate the expressions of claudin-5 and zonula occludens-1 expression.


Asunto(s)
4-Butirolactona/análogos & derivados , Benzofuranos/farmacología , Medicamentos Herbarios Chinos/farmacología , Glicósidos/farmacología , 4-Butirolactona/farmacología , Animales , Transporte Biológico , Barrera Hematoencefálica/efectos de los fármacos , Perros , Humanos , Células de Riñón Canino Madin Darby
11.
AAPS PharmSciTech ; 19(6): 2488-2498, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29948978

RESUMEN

To elucidate the compaction behavior of drug nanocrystals based composite particles (NP) during tabletting, the compaction behavior of binary mixtures of microcrystalline cellulose (MCC) and nanocrystal particles was investigated. The force-displacement correlation of mixtures containing different ratios of MCC and micronized NP was studied in order to explain the nature on densification of NP during compaction, and the resultant compaction curves (pressure as function of in-die thickness) were systemically analyzed to elucidate the most important mechanisms of volume reduction for MCC and NP in different stages of compaction. The results showed that the close compaction of individual MCC was relatively quickly achieved, and the drug NP particles could slide into the intrinsic void spaces between MCC microparticles. This was the reason that the particles size of MCC used in this study was significantly larger compared to that of drug NP. This interstitial rearrangement phenomenon of NP occurred on a typical time scale and was strongly dependent on the speed of compaction. This migration behavior occurred on void spaces of MCC inter-particles might be identified as an elastic stress relaxation mechanism and be helpful to dissolution of NP. MCC can effectively shield the NP from significant aggregation during compaction process.


Asunto(s)
Celulosa/química , Nanopartículas/química , Comprimidos/química , Excipientes/química , Tamaño de la Partícula , Presión
13.
AAPS PharmSciTech ; 18(5): 1572-1584, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27620195

RESUMEN

Poorly water-soluble drugs offer challenges in developing a formulation product with adequate bioavailability. This study took advantage of the features of nanocrystals and direct compression technologies to develop a novel solid self-nanodispersion delivery system for andrographolide (Andro) in order to increase its dissolution rate for enhancing bioavailability. Andro nanosuspensions (Andro-NS) with a particle size of about 500 nm were prepared by homogenization technology and further converted into dried nanocrystal particles (Andro-NP) via spray-drying. The solid self-nanodispersion delivery system (Andro-SNDS)-loaded Andro-NP was prepared via direct compression technology. The DSC and PXRD results demonstrated that the Andro nanocrystals retained its original crystallinity. The dissolution of the Andro-SNDS formulation was 85.87% in pure water over 30 min, better than those of the coarse Andro and physical mixture of Andro and stabilizer. And the C max (299.32 ± 78.54 ng/mL) and AUC0-∞ (4440.55 ± 764.13 mg/L · h) of the Andro-SNDS formulation were significantly higher (p < 0.05) than those of the crude Andro (77.52 ± 31.73 ng/mL and 1437.79 ± 354.25 mg/L · h). The AUC of the Andro-SNDS was 3.09 times as high as that of the crude Andro. This study illustrated a novel approach to combine the features of nanocrystals and composite particles used to improve oral bioavailability of poorly soluble drug.


Asunto(s)
Diterpenos , Sistemas de Liberación de Medicamentos , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacocinética , Disponibilidad Biológica , Desecación , Diterpenos/administración & dosificación , Diterpenos/farmacocinética , Composición de Medicamentos/métodos , Nanopartículas/química , Tamaño de la Partícula , Solubilidad
14.
AAPS PharmSciTech ; 18(7): 2744-2753, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28341935

RESUMEN

The objective of this study is to prepare a novel drug nanosuspension modified by a natural triterpenoid saponin (glycyrrhizin (GZ)) and evaluate its stability and redispersibility. A poorly soluble drug (andrographolide (AGE)) was used as a model drug. AGE nanosuspensions (AGE-NS) using GZ as natural stabilizer with mean particle size of 487 nm were firstly prepared by homogenization and converted into dried AGE nanosuspension powder (AGE-NP) by freeze-drying. It was found that GZ was able to prevent the aggregation of AGE nanocrystals and the freeze-dried AGE-NP could easily redisperse back to AGE-NS. It was related with special properties of GZ that possessed the interfacial property (37.02 ± 0.29 N/m) and electrostatic effect (-43.6 ± 0.9 mV) and could entrap AGE nanocrystals into its network structure. The freeze-dried AGE-NP/GZ exhibited excellent performance, compared with those combined with trehalose as matrix formers. The powder X-ray diffraction result demonstrated that GZ did not alter the AGE crystal state. The dissolution of AGE-NP/GZ (99.87%) was significantly enhanced, compared with the coarse AGE (42.35%). This study demonstrated that GZ could be used as a novel multifunctional stabilizer for production of drug nanosuspensions and provided a promising basis for further formulation development of poorly soluble drug.


Asunto(s)
Diterpenos/química , Ácido Glicirrínico/química , Estabilidad de Medicamentos , Liofilización , Nanopartículas/química , Polvos , Solubilidad , Suspensiones
15.
Zhongguo Zhong Yao Za Zhi ; 42(11): 2208-2213, 2017 Jun.
Artículo en Zh | MEDLINE | ID: mdl-28822170

RESUMEN

The dry quality of traditional Chinese medicine pills is the hot spot of pills research, because their quality has a crucial effect on the efficacy and development of dosage forms. Through literature research and statistical analysis, we would review the current problems on the drying of traditional Chinese medicine pills in this paper, and surrounding the evaluation system for traditional Chinese medicine pills, analyze the characteristics of common drying equipment and processes as well as their effect on quality of pills, discuss the problems in drying equipment and process as well as quality, and put forward the corresponding strategies, hoping to provide new ideas and new methods for the quality improvement of traditional Chinese medicine pills and quality standards.


Asunto(s)
Desecación , Medicamentos Herbarios Chinos/normas , Medicina Tradicional China , Control de Calidad , Estándares de Referencia
16.
Zhongguo Zhong Yao Za Zhi ; 42(19): 3826-3830, 2017 Oct.
Artículo en Zh | MEDLINE | ID: mdl-29235302

RESUMEN

The quality uniformity of traditional Chinese medicine (TCM) preparation is the base for guaranteeing the safety and effectiveness of clinical medication. At present, the quality of TCM preparation is uneven. At present, the same TCM preparation in different manufacturers, TCM preparations in the same manufacturer, and even different batches of a same TCM preparation in the same manufacturer have great differences in quality, which can not reach stability and uniformity. This paper would discuss the possible factors that influence the uniformity of quality in the whole process of pharmacy by means of consulting relevant literature on quality control of Chinese herbal preparations and analyzing the present situation and problems of the quality of TCM preparation. In addition, some strategies such as standardization of cultivation of TCM, processing standardization, standardization of pharmaceutical equipment, mixed batch feeding, and Quality by Design would be also put forward to provide references for the quality uniformity of TCM preparation.


Asunto(s)
Medicamentos Herbarios Chinos/normas , Medicina Tradicional China , Preparaciones de Plantas/normas , Control de Calidad
17.
Molecules ; 21(9)2016 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-27589712

RESUMEN

This study is aimed at seeking a nature saponin-based stabilizer for drug nanosuspensions. A poorly soluble drug (baicalein, BCL) was used as a model drug. BCL nanosuspensions with particle size of 156 nm were prepared by means of homogenization and converted into BCL nanocrystals (BCL-NC) stabilized with panax notoginseng saponins (PNS). It was found that PNS was able to prevent the aggregation of BCL-NS during storage and improve the redispersibility of BCL-NC after freeze-drying and spray-drying, compared with polymer stabilizer PVPK30. The freeze-dried and spray-dried BCL-NC with PNS exhibited excellent performance as evidenced by scanning_electron_microscope (SEM) analysis. It was the reason that PNS possessed the interfacial property (41.69 ± 0.32 mN/m) and electrostatic effect (-40.1 ± 1.6 mV), which could easily adsorb onto the surface of hydrophobic BCL nanocrystals and prevent from its aggregation. It is concluded that PNS can be used as an effective nature stabilizer for production of drug nanocrystals.


Asunto(s)
Flavanonas/química , Nanopartículas/química , Panax notoginseng/química , Saponinas/química , Solubilidad
18.
AAPS PharmSciTech ; 17(6): 1274-1284, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26689405

RESUMEN

To elucidate the roles of vitrification of stabilizers/matrix formers for the redispersibility of drug nanocrystal powder after solidification at storage stress, the influence of different drying methods and storage stresses on stability of drug nanocrystals was systemically investigated. A poorly soluble drug, baicalin, used as model drug was converted into baicalin nanocrystals (BCN-NC). The residual moisture contents of BCN-NC were applied at two different stress conditions defined as "conservative" (<1%) and "aggressive" (>1%), respectively. The influence of different stabilizers, matrix formers, and storage stresses on the redispersibility of BCN-NC powder was systemically investigated, respectively. The results showed that storage stresses had significantly influence the redispersibility of BCN-NC. Aggressive storage temperature and residual moisture could be unfavorable factors for stability of drug nanocrystals, due to the exacerbation of aggregation of BCN-NC induced by vitrification. It was demonstrated that vitrification of spray-dried BCN-NC was dependent on temperature and time. The polymeric stabilizers hydroxypropylmethylcellulose (HPMC) and sodium carboxymethyl starch (CMS-Na) with high glass transition temperature (T g) played more important role in protecting the BCN-NC from breakage during storage, compared to the surfactants Tween 80, D-α-tocopherol acid polyethylene glycol 1000 succinate (TPGS), or RH 40. Besides, the polyvinylpyrrolidone K30 (PVP K30) and lactose with high T g were effective matrix formers for preserving the redispersibility of BCN-NC. It was concluded that the vitrification transition of stabilizers/matrix formers could be responsible for aggregation of drug nanocrystals during storage, which was a time-dependent process. The suitable residual moisture contents (RMC) and T g were very important for preserving the stability of drug nanocrystals during storage.


Asunto(s)
Excipientes/química , Flavonoides/química , Nanopartículas/química , Vitrificación , Estabilidad de Medicamentos , Derivados de la Hipromelosa/química , Polietilenglicoles/química , Polímeros/química , Povidona/química , Polvos/química , Solubilidad , Almidón/análogos & derivados , Almidón/química , Temperatura , alfa-Tocoferol/química
19.
Molecules ; 20(8): 14849-59, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26287142

RESUMEN

To reveal the structural stabilities and transformation mechanism of rhynchophylline (RIN) and isorhynchophylline (IRN), HPLC and UPLC-Q-TOF-MS method were developed for the qualitative and quantitative analysis of the conversion rate. The method was validated for linearity, inter- and intra-day precisions, repeatability and stability. All the quantitative determination method validation results were satisfactory. Under the optimized chromatographic conditions, the effect of various heat temperatures, retention time, and solvent polarities on conversion rate and equilibrium were systematically investigated for the first time. Besides, a model relating the retention yield value and time-temperature was built to predict the t0.5 and Ea of the conversion rate by the Arrhenius equation. The experimental results proved to be in good accordance with the predicted values. Furthermore, UPLC-Q-TOF-MS analysis was performed to verify the transformation mechanism and provide valuable information for stability analysis of the conversion products.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Alcaloides Indólicos/química , Espectrometría de Masas/métodos , Calibración , Cinética , Oxindoles , Solventes , Temperatura , Factores de Tiempo
20.
Zhongguo Zhong Yao Za Zhi ; 40(23): 4715-20, 2015 Dec.
Artículo en Zh | MEDLINE | ID: mdl-27141689

RESUMEN

Drying is the critical link during pharmaceutical process of traditional Chinese medicine (TCM), which is directly related to the quality of drugs. The key to technology upgrading of pharmaceutical equipment in Chinese materia medica enterprise is the development of new drying techniques, which concerns the modernization of TCM. The study provides new ideas for the drying technology and equipment by means of reviewing the research status of drying process for the traditional Chinese medicinal materials and preparations, and analyzing the traditional and modern drying methods and equipment, as well as their existing problems and corresponding measures for the drying processes and equipment. In addition, this paper expounds the development trend of traditional Chinese medicinal materials and preparations of drying process and equipment.


Asunto(s)
Química Farmacéutica/normas , Medicamentos Herbarios Chinos/química , Medicina Tradicional China/normas , Plantas Medicinales/química , Química Farmacéutica/instrumentación , Química Farmacéutica/métodos , Humanos , Medicina Tradicional China/instrumentación
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