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1.
Pak J Pharm Sci ; 37(1(Special)): 235-243, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38747275

RESUMEN

Stimulus-responsive mesoporous silica nanoparticles (MSNs) have displayed great potentiality for controlled-release and targeted drug delivery. In the current work, a supercritical fluid method was utilized to successfully prepare cinnamon oil loaded into chitosan grafted MSNs (CO@CS-MSNs). The influencing factors of drug loads, such as pressure, temperature, impregnation time and depressure time, were investigated. The structure of CO@CS-MSNs was demonstrated with Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), scanning electron microscopy (SEM), thermogravimetry (TG) as well as X-ray diffraction (XRD). The drug release assays in vitro at various pH conditions displayed that CO@CS-MSNs had an excellent pH-responsive release behavior, which confirmed that CO was loaded successfully into the CO@CS-MSNs. The findings indicated that the supercritical fluid approach is a non-destructive and efficient approach for stimulus-responsive MSNs, which is expected to further expand its application range.


Asunto(s)
Dióxido de Carbono , Quitosano , Cinnamomum zeylanicum , Liberación de Fármacos , Nanopartículas , Dióxido de Silicio , Quitosano/química , Dióxido de Silicio/química , Nanopartículas/química , Concentración de Iones de Hidrógeno , Dióxido de Carbono/química , Porosidad , Cinnamomum zeylanicum/química , Portadores de Fármacos/química , Aceites Volátiles/química , Aceites Volátiles/administración & dosificación , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Microscopía Electrónica de Rastreo , Preparaciones de Acción Retardada
2.
Trials ; 22(1): 485, 2021 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-34496928

RESUMEN

BACKGROUND: Insomnia is a common but frequently overlooked sleep disorder after stroke, and there are limited effective therapies for insomnia following stroke. Traditional Chinese medicine (TCM), including acupuncture and the Chinese herbal medication (CHM) Suanzaoren decoction (SZRD), has been reported as an alternative option for insomnia relief after stroke in China for thousands of years. Here, this study aims to investigate the efficacy and safety of electroacupuncture (EA) in combination with SZRD in the treatment of insomnia following stroke. METHODS: A total of 240 patients with post-stroke insomnia will be included and randomized into four groups: the EA group, SZRD group, EA & SZRD group, and sham group. The same acupoints (GV20, GV24, HT7, and SP6) will be used in the EA group, EA & SZRD group, and sham group, and these patients will receive the EA treatment or sham manipulation every other day for 4 consecutive weeks. SZRD treatments will be given to participants in the SZRD group and EA & SZRD group twice a day for 4 consecutive weeks. The primary outcome measures include Pittsburgh Sleep Quality Index scores and polysomnography. Secondary outcome measures include the Insomnia Severity Index, the National Institutes of Health Stroke Scale, the Hospital Anxiety and Depression Scale, brain magnetic resonance imaging, functional magnetic resonance imaging, and nocturnal melatonin concentrations. The primary and secondary outcomes will be assessed at baseline (before treatment), during the 2nd and 4th weeks of the intervention, and at the 8th and 12th weeks of follow-up. Safety assessments will be evaluated at baseline and during the 4th week of the intervention. DISCUSSION: This study will contribute to assessing whether the combination of these two therapies is more beneficial for post-stroke insomnia than their independent use, and the results of this clinical trial will improve our understanding of the possible mechanisms underlying the effects of combination therapies. TRIAL REGISTRATION: Chinese Clinical Trials Register ChiCTR2000031413 . Registered on March 30, 2020.


Asunto(s)
Electroacupuntura , Trastornos del Inicio y del Mantenimiento del Sueño , Accidente Cerebrovascular , Medicamentos Herbarios Chinos , Electroacupuntura/efectos adversos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Trastornos del Inicio y del Mantenimiento del Sueño/etiología , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
3.
ACS Appl Mater Interfaces ; 10(43): 37651-37660, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30280560

RESUMEN

In semiconductor heterojunction, polarity critically governs the physical properties, with an impact on electronic or optoelectronic devices through the presence of pyroelectric and piezoelectric fields at the active heteropolar interface. In the present work, the abrupt O-polar ZnO/Ga-polar GaN heterointerface was successfully achieved by using high O/Zn ratio flux during the ZnO nucleation growth. Atomic-resolution high-angle annular dark-field and bright-field transmission electron microscopy observation revealed that this polarity inversion confines within one monolayer by forming the (0001) plane inversion domain boundary (IDB) at the ZnO/GaN heterointerface. Through theoretical calculation and topology analysis, the geometry of this IDB was determined to possess an octahedral Ga atomic layer in the interface, with one O/N layer symmetrically bonded at the tetrahedral site. The computed electronic structure of all considered IDBs revealed a metallic character at the heterointerface. More interestingly, the presence of two-dimensional (2D) hole gas (2DHG) or 2D electron gas (2DEG) is uncovered by investigating the chemical bonding and charge transfer at the heterointerface. This work not only clarifies the polarity control and interfacial configuration of the O-polar ZnO/Ga-polar GaN heterojunction but, more importantly, also gives insight into their further application on heterojunction field-effect transistors as well as hybrid ZnO/GaN optoelectronic devices. Moreover, such polarity control at the monolayer scale might have practical implications for heterojunction devices based on other polar semiconductors.

4.
J Chem Phys ; 145(21): 211902, 2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-28799402

RESUMEN

We have studied nucleation and growth of Dy islands on the basal plane of graphite at 300 K using scanning tunneling microscopy, density functional theory (DFT) in a form that includes van der Waals interactions, and analytic theory. The interaction of atomic Dy with graphite is strong, while the diffusion barrier is small. Experiment shows that at 300 K, the density of nucleated islands is close to the value predicted for homogeneous nucleation, using critical nucleus size of 1 and the DFT-derived diffusion barrier. Homogeneous nucleation is also supported by the monomodal shape of the island size distributions. Comparison with the published island density of Dy on graphene shows that the value is about two orders of magnitude smaller on graphite, which can be attributed to more effective charge screening in graphite. The base of each island is 3 atomic layers high and atomically ordered, forming a coincidence lattice with the graphite. Islands resist coalescence, probably due to multiple rotational orientations associated with the coincidence lattice. Upper levels grow as discernible single-atom layers. Analysis of the level populations reveals significant downward interlayer transport, which facilitates growth of the base. This island shape is metastable, since more compact three-dimensional islands form at elevated growth temperature.

6.
Zhongguo Zhen Jiu ; 34(1): 3-8, 2014 Jan.
Artículo en Chino | MEDLINE | ID: mdl-24673043

RESUMEN

OBJECTIVE: To compare the efficacy of different points combination in the treatment of menopausal insomnia. METHODS: Ninety-six cases of menopausal insomnia were randomized into 3 groups, Xinshu (BL 15), Shenshu (BL 23), Sishencong (EX-HN 1), Shenmen (HT 7), Sanyinjiao (SP 6) were chosen in the restore interaction between the heart and the kidney group (group A, 32 cases); Zhaohai (KI 6), Jiaoxin (KI 8), Shenmai (BL 62), Pucan (BL 61) were chosen in the acupuncturing qiao mai group (group B, 32 cases); auricular Shenmen (TF4) and sensitive spot at the distribution area of auricular vagus nervus were chosen in the ear acupuncture group (group C, 32 cases). Six days made one session and the treatments were finished after 4 courses. The polysomnography (PSG) and Pittsburgh sleep quality index (PSQI) were employed before and after treatment to evaluate the alleviation of insomnia. RESULTS: The parameters of the sleep latency (SL), rapid wave sleep latency (RL) and sleep efficiency (SE) were significantly improved in the three groups, and the differences were statistically significant (P < 0.05, P < 0.01). The SL and awaking time (AT) in group C [SL (401.08 +/- 16.54) min and AT (4.87 +/- 2.64) times] were significantly superior to those in the other two groups [SL (50.36 +/- 18.47) min, (54.87 +/- 20.92) min, AT (5.98 +/- 2.11) times, (6.13 +/- 3.04) times, all P < 0.05]. The S(3+4) (%) in group C was also significantly higher than those in the other two groups (both P < 0.05). It was indicated by PSQI that the sleep quality of group C (0.78 +/- 0.12) was significantly superior to that in group B (1.32 +/- 0.29), the total score and cured and markedly effective rate in group C [(4.34 +/- 1.43), 68.8% (22/32)] were superior to those in group A [(7.48 +/- 3.09), 53.1% (17/32), both P < 0.05]. CONCLUSION: Ear acupuncture has a better curative effect than the restore interaction between the heart and the kidney group and acupuncturing qiao mai group, it is worth of being promoted.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura , Menopausia/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Adulto , Femenino , Humanos , Persona de Mediana Edad , Sueño , Resultado del Tratamiento
7.
J Chem Phys ; 139(22): 224702, 2013 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-24329077

RESUMEN

The adsorption, diffusion, and molecular dissociation of hydrogen on the biaxially strained Mg (0001) surface have been systematically investigated by the first principle calculations based on density functional theory. When the strain changes from the compressive to tensile state, the adsorption energy of H atom linearly increases while its diffusion barrier linearly decreases oppositely. The dissociation barrier of H2 molecule linearly reduces in the tensile strain region. Through the chemical bonding analysis including the charge density difference, the projected density of states and the Mulliken population, the mechanism of the strain effect on the adsorption of H atom and the dissociation of H2 molecule has been elucidated by an s-p charge transfer model. With the reduction of the orbital overlap between the surface Mg atoms upon the lattice expansion, the charge transfers from p to s states of Mg atoms, which enhances the hybridization of H s and Mg s orbitals. Therefore, the bonding interaction of H with Mg surface is strengthened and then the atomic diffusion and molecular dissociation barriers of hydrogen decrease accordingly. Our works will be helpful to understand and to estimate the influence of the lattice deformation on the performance of Mg-containing hydrogen storage materials.

8.
J Phys Condens Matter ; 25(48): 485002, 2013 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-24162383

RESUMEN

We have characterized the (010) surface of Gd5Ge4 using scanning tunneling microscopy (STM) and x-ray photoelectron spectroscopy. Data from different samples have the following features in common: (1) the surface composition equals the bulk composition to within 5 at.%, both after ion etching and after annealing at temperatures of 400-1200 K; and (2) the surface exhibits terraces of two types. The height of the steps between similar terraces corresponds well to the separation between equivalent layers along the <010> direction in the bulk structure. Density functional theory (DFT) shows that the surface energy of the (0001) plane of hexagonal close-packed Gd is lower than that of the (111) plane of diamond-type Ge, suggesting that surfaces of Gd5Ge4 (for comparable density) should be rich in Gd. Indeed, DFT shows that among the bulk terminations of Gd5Ge4, a pure Ge termination is not favored. Each of the three remaining terminations (two pure Gd and one mixed, Gd-Ge) has its minimum surface energy in a different range of the possible Gd chemical potentials, indicating that different terminations may be stable under different conditions. DFT shows that the heights of the steps between dissimilar terraces, measured in STM, are consistent with the two pure Gd terminations.

9.
Exp Lung Res ; 37(10): 627-32, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22044439

RESUMEN

Short-term exposure to cigarette smoke (CS) introduces an abundance of free radicals into the lungs, causing oxidative stress and inflammation. CS is an important risk factor related to the pathogenesis of several pulmonary diseases, especially chronic obstructive pulmonary disease. Black coral (BC) is a marine biomaterial commonly used for cigarette holders in southeast China. The purpose of the present study was to evaluate the in vivo bioactivity of BC extract (BCE). Groups of mice (male Kunming) were subjected to ultrasonic atomizing inhalation of BCE (0.3, 1.5, and 3 mg/mL) before being exposed to CS (10 cigarettes per day for 4 days). The control group and the CS group were administered normal saline rather than BCE prior to CS exposure. Superoxide dismutase (SOD), malondialdehyde (MDA), and myeloperoxidase (MPO) levels were measured in lung homogenates. Histologic and morphologic studies of the right upper lung were performed. SOD activity increased 1.32 times in the CS+BCE (3 mg/mL) group (P < .001) compared with the CS group. The MDA content increased 4% (P < .001) in the CS+BCE (3 mg/mL) group compared with the control group. MPO was reduced 40% in the CS+BCE (3 mg/mL) group compared with the CS group (P < .001). Histologic analysis revealed decreased inflammation in the BCE group compared with the CS group. These results suggest that BCE has antioxidant and anti-inflammatory activity in vivo. BCE may protect against lung injury in smokers.


Asunto(s)
Antozoos/química , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Neumonía/tratamiento farmacológico , Neumonía/metabolismo , Fumar/efectos adversos , Animales , Antiinflamatorios/química , Antioxidantes/química , China , Masculino , Malondialdehído/metabolismo , Ratones , Peroxidasa/metabolismo , Neumonía/etiología , Superóxido Dismutasa/metabolismo
10.
Mar Drugs ; 9(5): 863-878, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21673895

RESUMEN

Black corals (BC) have been used for a long time in Chinese medicine, and may have some pharmaceutical functions when used as material for cigarette holders in southeast China. This study is aimed to investigate the bioactivities of volatile constituents in BC and to explore the folklore behind the use of BC cigarette holders (BCCHs). We extracted the volatile constituents of BC by supercritical fluid extraction (SFE) with carbon dioxide (CO2-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 15 components were reliably identified in BC and found to be biologically active. These included triethyl phosphate, butylated hydroxytoluene, cedrol, n-hexadecanoic acid, squalene, and cholesterol. Meanwhile 13 inorganic elements (P, Ca, Mg, S, B, Si, Fe, Cu, Zn, Ba, etc.) were determined by inductively coupled plasma spectrometer (ICPS). In the bioactivity tests, the BC extract (BCE) showed a scavenging activity of 2,2-diphenyl-1-picrylhydrazyl free radicals and hydroxyl radicals by phenanthroline-Fe (II) oxidation and moderate inhibition of Gram-positive microorganisms. The antioxidant and antimicrobial activities of BC, which are related to the active chemical composition, may explain the perceived benefit for cigarette smokers who use BCCHs.


Asunto(s)
Antozoos/química , Animales , Antioxidantes/farmacología , Cromatografía con Fluido Supercrítico , Elementos Químicos , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno/metabolismo , Fumar , Compuestos Orgánicos Volátiles/análisis
11.
Nat Prod Commun ; 5(10): 1673-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21121271

RESUMEN

The essential oils from leaves, twigs and stems of large trees and shrub-like trees of Thuja sutchuenensis were extracted by hydrodistillation and supercritical fluid extraction, and analyzed by GC and GC-MS. The essential oil composition differed significantly among the three organs, as well as between large trees and shrub-like trees. Furthermore, consistent with the eastern Asia-North American disjunct distribution of the genus, many differences in the essential oil composition between T. sutchuenensis and other Thuja species were apparent. The essential oils exhibited a certain degree of antifungal activity against six strains of human pathogenic fungi.


Asunto(s)
Antifúngicos/aislamiento & purificación , Aceites Volátiles/química , Thuja/química , China , Especies en Peligro de Extinción , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Árboles/química
12.
Zhong Yao Cai ; 29(4): 383-7, 2006 Apr.
Artículo en Chino | MEDLINE | ID: mdl-16913495

RESUMEN

The technics of supercritical carbon dioxide extraction of Brucea Javanica for injection oil was studied. The effects of the conditions of extraction and separation on extraction oil yield and quality were investigated and the effects of extraction pressure and separation pressure on acid number of the oil were discussed. So the optimal condition of this method was determined. With a quality evaluation, the Brucea Javanica oil extracted with supercritical CO2 agreed with the quality standard of refined Brucea Javanica oil for injection. This method shows sufficiently the advantages of supercritical CO2 extraction applied in the extraction of traditional Chinese medicine.


Asunto(s)
Brucea/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Plantas Medicinales/química , Tecnología Farmacéutica/métodos , Dióxido de Carbono , Cromatografía con Fluido Supercrítico/métodos , Medicamentos Herbarios Chinos/normas , Ácidos Grasos/análisis , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Aceites de Plantas/normas , Presión , Temperatura
13.
Zhong Yao Cai ; 28(4): 334-7, 2005 Apr.
Artículo en Chino | MEDLINE | ID: mdl-16104514

RESUMEN

To optimize the extraction process for zhuyun 3# pill by supercritical CO2. Five kinds of supercritical CO2 extraction method had been applied. The methods were estimated by the pharmacological results and the content of flovone. The best extraction process for zhuyun 3# pill was that Lüzhenzi, Baizhu and Xuduan were extracted with supercritical CO2 and the residue was estracted by water, the other five kinds of medicinal materials were extracted by water.


Asunto(s)
Cromatografía con Fluido Supercrítico , Medicamentos Herbarios Chinos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Plantas Medicinales/química , Aborto Espontáneo/prevención & control , Animales , Dióxido de Carbono , Cromatografía con Fluido Supercrítico/métodos , Combinación de Medicamentos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Femenino , Flavonas , Flavonoides/análisis , Masculino , Ratas , Ratas Sprague-Dawley , Tecnología Farmacéutica/métodos , Agua
14.
Zhong Yao Cai ; 27(3): 177-80, 2004 Mar.
Artículo en Chino | MEDLINE | ID: mdl-15272780

RESUMEN

The extraction of fatty oils from bee pollen with supercritical CO2 was studied. The effects of extraction pressure, extraction temperature and the grinding size of the bee pollen on the yields were discussed. The optimal condition of this method was: extraction pressure 30MPa,extraction temperature 55 degrees C, separator I pressure 14MPa, separator I temperature 45 degrees C, separator II pressure 6MPa, separator II temperature 40 degrees C, extraction period 2 hours. Compared with the traditional solvent extraction, this method had some virtues, such as shortening the extraction period greatly, escaping oxidation of unsaturated fatty acid, and the products from which having better quality. With a GC-MS analysis, the main composition of the fatty oil from the bee pollen was: oleic acid, palmitic acid, linoic acid, pentacosane, octacosane and so on. The contents of alpha-linolenic acid in the fatty oils from separator I and separator II were 42% and 8.8%, which differed greatly. It proved that this method succeeded in extraction, separating and enriching alpha-linolenic acid.


Asunto(s)
Abejas , Aceites de Plantas/química , Polen/química , Ácido alfa-Linolénico/análisis , Animales , Dióxido de Carbono , Cromatografía con Fluido Supercrítico/métodos , Cromatografía de Gases y Espectrometría de Masas , Ácido Linoleico/aislamiento & purificación , Ácido Oléico/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Presión , Temperatura , Ácido alfa-Linolénico/aislamiento & purificación
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