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1.
Plant J ; 120(2): 429-444, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39052425

RESUMEN

The tiller angle is an important agronomic trait that determines plant architecture and grain yield in rice (Oryza sativa L.). However, the molecular regulation mechanism of the rice tiller angle remains unclear. Here, we identified a rice tiller angle gene, LARGE TILLER ANGLE 1 (LATA1), using the MutMap approach. LATA1 encodes a C3H2C3-type RING zinc finger E3 ligase and the conserved region of the RING zinc finger is essential for its E3 activity. LATA1 was highly expressed in the root and tiller base and LATA1-GFP fusion protein was specifically localized to the nucleus. The mutation of LATA1 significantly reduced indole-3-acetic acid content and attenuated lateral auxin transport, thereby resulting in defective shoot gravitropism and spreading plant architecture in rice. Further investigations found that LATA1 may indirectly affect gravity perception by modulating the sedimentation rate of gravity-sensing amyloplasts upon gravistimulation. Our findings provide new insights into the molecular mechanism underlying the rice tiller angle and new genetic resource for the improvement of plant architecture in rice.


Asunto(s)
Gravitropismo , Ácidos Indolacéticos , Oryza , Proteínas de Plantas , Ubiquitina-Proteína Ligasas , Oryza/genética , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Oryza/enzimología , Ácidos Indolacéticos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Gravitropismo/genética , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Mutación
2.
Clin Exp Nephrol ; 28(8): 740-750, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38709377

RESUMEN

OBJECTIVE: To investigate the predictors and establish a nomogram model for the prediction of the response to treatment in primary membranous nephropathy (PMN) with nephrotic syndrome (NS). METHODS: The clinical, laboratory, pathological and follow-up data of patients with biopsy-proven membranous nephropathy at the Affiliated Hospital of Qingdao University were collected. A total of 373 patients were randomly assigned into development group (n = 262) and validation group (n = 111). Logistic regression analysis was performed in the development group to determine the predictors of treatment response. A nomogram model was established based on the multivariate logistic regression analysis and validated in the validation group. The C-index and calibration plots were used for the evaluation of the discrimination and calibration performance, respectively. RESULTS: Serum albumin levels (OR = 1.151, 95% CI 1.078-1.229, P < 0.001) and glomerular C3 deposition (OR = 0.407, 95% CI 0.213-0.775, P = 0.004) were identified as independent predictive factors for treatment response in PMN with NS, then a nomogram was established combining the above indicators and treatment regimen. The C-indices of this model were 0.718 (95% CI 0.654-0.782) and 0.789 (95% CI 0.705-0.873) in the development and validation groups, respectively. The calibration plots showed that the predicted probabilities of the model were consistent with the actual probabilities (P > 0.05), which indicated favorable performance of this model in predicting the treatment response probability. CONCLUSIONS: Serum albumin levels and glomerular C3 deposition were predictors for treatment response of PMN with NS. A novel nomogram model with good discrimination and calibration was constructed to predict treatment response probability at an early stage.


Asunto(s)
Glomerulonefritis Membranosa , Síndrome Nefrótico , Nomogramas , Humanos , Glomerulonefritis Membranosa/tratamiento farmacológico , Glomerulonefritis Membranosa/complicaciones , Masculino , Síndrome Nefrótico/complicaciones , Síndrome Nefrótico/tratamiento farmacológico , Femenino , Persona de Mediana Edad , Adulto , Resultado del Tratamiento , Complemento C3/análisis , Albúmina Sérica Humana/análisis , Estudios Retrospectivos , Albúmina Sérica/análisis , Valor Predictivo de las Pruebas , Modelos Logísticos , Inmunosupresores/uso terapéutico , Reproducibilidad de los Resultados , China
3.
Math Biosci Eng ; 20(11): 19584-19616, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-38052616

RESUMEN

In this paper, we revisit a discrete prey-predator model with the Allee effect in prey to find its more complex dynamical properties. After pointing out and correcting those known errors for the local stability of the unique positive fixed point $ E_*, $ unlike previous studies in which the author only considered the codim 1 Neimark-Sacker bifurcation at the fixed point $ E_*, $ we focus on deriving many new bifurcation results, namely, the codim 1 transcritical bifurcation at the trivial fixed point $ E_1, $ the codim 1 transcritical and period-doubling bifurcations at the boundary fixed point $ E_2, $ the codim 1 period-doubling bifurcation and the codim 2 1:2 resonance bifurcation at the positive fixed point $ E_* $. The obtained theoretical results are also further illustrated via numerical simulations. Some new dynamics are numerically found. Our new results clearly demonstrate that the occurrence of 1:2 resonance bifurcation confirms that this system is strongly unstable, indicating that the predator and the prey will increase rapidly and breakout suddenly.

4.
J Agric Food Chem ; 71(48): 18660-18673, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38053506

RESUMEN

Carotenoids are essential for photosynthesis and photoprotection in photosynthetic organisms, which are widely used in food coloring, feed additives, nutraceuticals, cosmetics, and pharmaceuticals. Carotenoid biofortification in crop plants or algae has been considered as a sustainable strategy to improve human nutrition and health. However, the regulatory mechanisms of carotenoid accumulation are still not systematic and particularly scarce in algae. This article focuses on the regulatory mechanisms of carotenoid accumulation in plants and algae through regulatory factors (transcription factors and regulatory proteins), demonstrating the complexity of homeostasis regulation of carotenoids, mainly including transcriptional regulation as the primary mechanism, subsequent post-translational regulation, and cross-linking with other metabolic processes. Different organs of plants and different plant/algal species usually have specific regulatory mechanisms for the biosynthesis, storage, and degradation of carotenoids in response to the environmental and developmental signals. In plants and algae, regulators such as MYB, bHLH, MADS, bZIP, AP2/ERF, WRKY, and orange proteins can be involved in the regulation of carotenoid metabolism. And many more regulators, regulatory networks, and mechanisms need to be explored. Our paper will provide a basis for multitarget or multipathway engineering for carotenoid biofortification in plants and algae.


Asunto(s)
Plantas , Factores de Transcripción , Humanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Plantas/genética , Plantas/metabolismo , Carotenoides/metabolismo , Fotosíntesis , Metabolismo de los Lípidos , Regulación de la Expresión Génica de las Plantas
5.
Sci Rep ; 13(1): 20575, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996462

RESUMEN

Using a semidiscretization method, we derive in this paper a discrete slow-fast predator-prey system with ratio-dependent functional response. First of all, a detailed study for the local stability of fixed points of the system is obtained by invoking an important lemma. In addition, by utilizing the center manifold theorem and the bifurcation theory some sufficient conditions are obtained for the transcritical bifurcation and Neimark-Sacker bifurcation of this system to occur. Finally, with the use of Matlab software, numerical simulations are carried out to illustrate the corresponding theoretical results and reveal some new dynamics of the system. Our results clearly demonstrate that the system is very sensitive to its fast time scale parameter variable.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37019038

RESUMEN

Natural flavors and fragrances or their extracts have been widely used in a large variety of areas, including food, cosmetic, and tobacco industrial processes, among others. The compositions and intrinsic attributes of flavors and fragrances were related to many factors, such as species, geographical origin, planting environment, storage condition, processing method, and so on. This not only increased the difficulty in analyzing the product quality of flavors and fragrances, but also challenged the idea of "quality-by-design (QbD)". This work proposed an integrated strategy for precise discovery of differential compounds among different classes and subsequent quality analysis of complex samples through flavors and fragrances used in tobacco industry as examples. Three pretreatment methods were first inspected to effectively characterize the sample compositions, including direct injection (DI), thermal desorption (TD), and stir bar sorptive extraction (SBSE)-TD, coupled with gas chromatography-mass spectrometry (GC-MS) analysis to obtain characteristic information of samples of flavors and fragrances. Then, principal component analysis (PCA) was applied to discover the relation and difference between chromatographic fingerprints and peak table data once significant components were recognized in a holistic manner. Model population analysis (MPA) was then used to quantitatively extract the characteristic chemicals representing the quality differences among different classes of samples. Some differential marker compounds were discovered for difference analysis, including benzyl alcohol, latin acid, l-menthol acid, decanoic acid ethyl ester, vanillin, trans-o-coumaric acid, benzyl benzoate, and so on. Furthermore, partial least squares-discriminant analysis (PLS-DA) and support vector machine (SVM) were respectively applied to construct multivariate models for evaluation of quality differences and variations. It was found that the accuracy attains to 100% for sample classification. With the help of optimal sample pretreatment technique and chemometric methods, the strategy for quality analysis and difference discovery proposed in this work can be widely delivered to more areas of complex plants with good interpretability and high accuracy.


Asunto(s)
Quimiometría , Odorantes , Odorantes/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos
7.
Medicine (Baltimore) ; 101(47): e31894, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36451449

RESUMEN

BACKGROUND: The role of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKIs) in improving the prognostic outcome of non-small cell lung cancer (NSCLC) cases harboring EGFR mutation following radical surgery is still controversial. This work focused on comparing EGFR-TKIs and adjuvant chemotherapy (ACT) or placebo in treating NSCLC cases, specifically on those with EGFR-mutant, being in the stage of IB-IIIA and possibly gained benefits from the above treatment after radical resection. METHODS: The Cochrane Library, MEDLINE, and Embase databases were searched to identify eligible clinical trials; two authors were responsible for screening the results. The primary outcomes were evaluated by disease-free survival (DFS) and overall survival (OS) based on hazard ratios (HRs) and a relevant 95% confidence interval (CI). RESULTS: The literature search yielded twelve eligible studies, including four retrospective cohort studies and eight randomized controlled trials (RCTs) that enrolled 1694 cases and were of acceptable quality. In patients receiving adjuvant EGFR-TKIs compared with ACT or placebo treatment, HR regarding DFS was 0.47 (95% CI: 0.40, 0.55), whereas the OS rate was 0.74 (95% CI: 0.58, 0.95). For patients who received adjuvant EGFR-TKIs in combination with conventional chemotherapy compared to chemotherapy, the efficiency was significantly enhanced, with the HR for DFS being 0.29 (95% CI: 0.15, 0.58) and that for OS being 0.51 (95% CI: 0.25, 1.04), separately. CONCLUSION: For NSCLC cases who had EGFR mutations and surgery, adjuvant EGFR-TKI combined with chemotherapy achieved superior effect over chemotherapy or placebo with reference to DFS and may prolong the OS up to some extent.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Adyuvantes Farmacéuticos , Inhibidores de Proteínas Quinasas/uso terapéutico , Adyuvantes Inmunológicos , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/cirugía , Mutación
8.
J Asian Nat Prod Res ; 20(2): 117-121, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28644689

RESUMEN

Two new prenylflavonoids, morusalbols A and B (1 and 2), were isolated from the branches and leaves of Morus alba, together with three known compounds, kuwanon C (3), morusin (4), morusinol (5). The structures of these two prenylflavonoids were elucidated by extensive analyzes of the spectroscopic data.


Asunto(s)
Flavonoides/aislamiento & purificación , Morus/química , Flavonoides/química , Flavonoides/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química
9.
Drug Deliv ; 22(3): 351-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24467528

RESUMEN

Cucurbitacin B (Cu B), a potent anti-cancer agent, suffers with the problems of water-insoluble, gastrointestinal side effects and non-specific toxicity via oral administration and drawbacks in patient's compliance and acceptance through injections. An integration of nanoscale carriers with mucoadhesive buccal films drug delivery system would resolve these issues effectively with greater therapeutic benefits and clinical significance. Thus, the drug loaded mucoadhesive buccal film was developed and characterized in this study and the carboxymethyl chitosan (CCS) was chosen as a bioadhesive polymer, glycerol was chosen as a plasticizer and phospholipid-bile salts-mixed micelles (PL-BS-MMs) was selected as the nanoscale carriers. The CCS-films containing Cu B loaded PL-SDC-MMs was evaluated for the mechanical properties, mucoadhesion properties, in vitro water-uptake, in vitro release and morphological properties, respectively. The optimal CCS-films containing Cu B loaded PL-SDC-MMs was easily reconstituted in a transparent and clear solution with spherical micelles in the submicron range. The in vivo study revealed a greater and more extended release of Cu B from nanoscale CCS-films compared to that from a conventional CCS films (C-CCS-films) and oral marketed tablet (Hulusupian). The absorption of Cu B from CCS-films containing Cu B loaded PL-SDC-MMs resulted in 2.69-fold increased in bioavailability as compared to conventional tablet formulation and 10.46 times with reference to the C-CCS-films formulation. Thus, this kind of mucoadhesive buccal film might be an alternative safe route for delivery of Cu B with better patient compliance and higher bioavailability for the treatments.


Asunto(s)
Ácidos y Sales Biliares/química , Portadores de Fármacos/química , Mucosa Bucal/metabolismo , Fosfolípidos/química , Adhesivos Tisulares/química , Triterpenos/administración & dosificación , Adhesividad , Administración Bucal , Animales , Química Farmacéutica , Técnicas In Vitro , Masculino , Micelas , Mucosa Bucal/efectos de los fármacos , Tamaño de la Partícula , Conejos , Propiedades de Superficie , Porcinos , Triterpenos/efectos adversos , Triterpenos/sangre , Triterpenos/química
10.
Chin J Nat Med ; 12(2): 108-13, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24636060

RESUMEN

The anti-bacterial activities of three types of di-O-caffeoylquinic acids (diCQAs) in Lonicera japonica flowers, a traditional Chinese medicine (TCM), on Bacillus shigae growth were investigated and compared by microcalorimetry. The three types of diCQAs were 3, 4-di-O-caffeoylquinic acid (3, 4-diCQA), 3, 5-di-O-caffeoylquinic acid (3, 5-diCQA), and 4, 5-di-O-caffeoylquinic acid (4, 5-diCQA). Some qualitative and quantitative information of the effects of the three diCQAs on metabolic power-time curves, growth rate constant k, maximum heat-output power Pm, and the generation time tG, total heat output Qt, and growth inhibitory ratio I of B. shigae were calculated. In accordance with a thermo-kinetic model, the corresponding quantitative relationships of k, Pm, Qt, I and c were established. Also, the half-inhibitory concentrations of the drugs (IC50) were obtained by quantitative analysis. Based on the quantity-activity relationships and the IC50 values, the sequence of inhibitory activity was 3, 5-diCQA > 4, 5-diCQA > 3, 4-diCQA. The results illustrate the possibility that the caffeoyl ester group at C-5 is the principal group that has a higher affinity for the bacterial cell, and that the intramolecular distance of the two caffeoyl ester groups also has an important influence on the anti-bacterial activities of the diCQAs.


Asunto(s)
Antibacterianos/farmacología , Bacillus/efectos de los fármacos , Ácido Clorogénico/análogos & derivados , Medicamentos Herbarios Chinos/farmacología , Lonicera/química , Monosacáridos/farmacología , Ácido Quínico/análogos & derivados , Bacillus/crecimiento & desarrollo , Ácido Clorogénico/química , Ácido Clorogénico/farmacología , Flores/química , Concentración 50 Inhibidora , Monosacáridos/química , Ácido Quínico/química , Ácido Quínico/farmacología
11.
Int J Nanomedicine ; 9: 505-15, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24531119

RESUMEN

The aim of this study was to investigate the feasibility of using spray granulation as a drying method to convert phospholipid (PL)-sodium deoxycholate (SDC)-mixed micelles (MMs) containing a water-insoluble drug to a solid dosage form and to evaluate how drugs with significantly different physicochemical properties affect the spray granulation process and subsequent in vitro and in vivo processes. Cucurbitacin B (Cu B) and glycyrrhizin (GL) were used as the model drugs. After spray granulation, the dried Cu B-PL/SDC-MM powder was completely redispersible within 15 minutes in vitro. Meanwhile, the area under the curve during 24 hours (AUC0-24) and peak serum concentration from the dried powder were significantly (P<0.05) lower than the values from Cu B-PL/SDC-MMs in vivo. However, a better result was obtained for GL, ie, the drug was redispersed completely within 5 minutes in vitro. Further, absorption from the dried GL-PL/SDC-MM powder was increased to the same level as that for GL-PL/SDC-MMs in vivo compared with the control group. The difference in these results can be found in Cu B and GL. Cu B nanoparticles reagglomerated when released, resulting in slower redispersibility and less absorption compared with the original PL-SDC-MMs. However, no agglomeration or delay was observed for GL. A possible explanation is the difference in surface hydrophobicity between Cu B and GL. The results of this study not only show that spray granulation is an effective drying technique that can complement spray-drying and freeze-drying, but also confirm that the physicochemical properties of a drug have a significant influence on the in vitro and in vivo performance of the dried powder obtained after spray granulation.


Asunto(s)
Nanopartículas/química , Administración Oral , Animales , Ácidos y Sales Biliares/química , Disponibilidad Biológica , Química Farmacéutica/métodos , Desecación/métodos , Perros , Estabilidad de Medicamentos , Ácido Glicirrínico/administración & dosificación , Ácido Glicirrínico/química , Ácido Glicirrínico/farmacocinética , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Micelas , Nanomedicina , Nanopartículas/administración & dosificación , Nanopartículas/ultraestructura , Tamaño de la Partícula , Fosfolípidos/química , Polvos/química , Solubilidad , Triterpenos/administración & dosificación , Triterpenos/química , Triterpenos/farmacocinética
12.
Pharmazie ; 69(11): 792-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25985572

RESUMEN

Cucurbitacin B (Cu B), formulated in the phospholipid-bile salts-mixed micelles (PL-BS-MMs), was transformed into dry powders by solidification process. Solidification methods for this transformation included freeze-drying, spray-drying or vacuum-drying, and different grades of process parameters called conservative, moderate and aggressive have been used in each solidification method, respectively. Saccharides (mannose, trehalose and glucose), polyethylene glycol (PEG) and mucoadhesive water-soluble polymers (carrageenan, hydroxpropylmethylcellulose (HPMC) and gelatin) were selected as the stabilizer, respectively. The influence of different stabilizers on the redispersibility of solid Cu B-PL/SDC-MMs was systemically investigated, such as the redispersibility index (RDI). The results showed that there were significant differences in RDI from samples stabilized by different stabilizers. The solid Cu B-PL/SDC-MMs stabilized by mucoadhesive water-soluble polymers (carrageenan, HPMC and gelatin) have better redispersibility under different solidification approaches, compared with those samples stabilized by other stabilizers. The results indicated that the mucoadhesive water-soluble polymers could effectively counter various stresses from the solidification process and prevent the nanocrystal surface from agglomeration. The combined action between steric hindrance and increased viscosity appeared to effectively avoid irreversible particle aggregation.


Asunto(s)
Ácidos y Sales Biliares/química , Fosfolípidos/química , Polímeros/química , Adhesivos Tisulares/química , Desecación , Liofilización , Micelas , Membrana Mucosa , Solubilidad
13.
J Drug Target ; 21(2): 180-7, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23373544

RESUMEN

Schisandrae lignans (SL) have been well proven to possess hepatoprotective effect against the hepatic dysfunction induced by various chemical hepatotoxins. Deoxyschisandrin (DA) and schisantherin A (SA) are both considered as the major active components in SL. The objective of the study was to prepare and evaluate Schisandra lignans (composed of DA and SA)-loaded enteric nanoparticles produced by a novel toxic solvent-free modified spontaneous emulsification solvent diffusion (SESD) method. An organic Schisandra lignans/Eudragit(®) S100 solution was injected into an aqueous poloxamer 188 solution under a agitation. The nanoparticles were characterized with respect to particle size distribution, morphology, encapsulation efficiency (EE) and physical stability of the drug, wettability, in vitro release and in vivo bioavailability. Nanoparticles with a smooth surface and dense structure were obtained with high EE (EE(DA) >90%; EE(SA) >85%). The drug was in a noncrystalline state in the matrix and physically stable for 120 days at room temperature. In vitro drug release study, the drug dissolution rate from the nanoparticles was significantly enhanced compared to the physical mixture and to the pure drug; the release profile of the nanoparticles was stable after 120 days. The appropriate size of nanoparticles (~93 nm), the solubilization of the surfactant, the noncrystalline state of the drug in the matrix and the fast dissolution rate contributed to a significantly enhanced oral bioavailability from the nanoparticles when compared to pure drug suspension.


Asunto(s)
Ciclooctanos/aislamiento & purificación , Ciclooctanos/farmacología , Portadores de Fármacos/química , Lignanos/aislamiento & purificación , Lignanos/farmacología , Nanopartículas/química , Compuestos Policíclicos/aislamiento & purificación , Compuestos Policíclicos/farmacología , Schisandra/química , Animales , Disponibilidad Biológica , Cristalización , Ciclooctanos/administración & dosificación , Ciclooctanos/farmacocinética , Composición de Medicamentos , Estabilidad de Medicamentos , Lignanos/administración & dosificación , Lignanos/farmacocinética , Masculino , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Compuestos Policíclicos/administración & dosificación , Compuestos Policíclicos/farmacocinética , Ratas , Ratas Wistar , Solubilidad , Propiedades de Superficie , Humectabilidad
14.
Int J Pharm ; 387(1-2): 139-46, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20005937

RESUMEN

The objective of this study was to prepare oxymatrine-phospholipid complex (OMT-PLC) to enhance oral bioavailability of oxymatrine. A central composite design approach was used for process optimization. The physicochemical properties of the complex obtained by optimal parameters were investigated by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD) and N-octanol/water partition coefficient. Compared with those of the physical mixture or oxymatrine, the hepatocytes permeability of oxymatrine-phospholipid complexes was studied. The concentrations of oxymatrine after oral administration of OMT-PLC at different time in rats were determined by HPCE. Multiple linear regression analysis for process optimization revealed that the acceptable OMT-PLC was obtained wherein the optimal values of X(1), X(2) and X(3) were 3, 60 degrees C and 3 h, respectively. The oxymatrine and phospholipids in the OMT-PLC were combined by non-covalent bond, not forming a new compound. The better hepatocytes permeability was obtained by the OMT-PLC. Pharmacokinetic parameters of the complex in rats were T(max) 2.17 h, C(max) 0.437 microg ml(-1), AUC(0-infinity) 9.43 microg h ml(-1), respectively. The bioavailability of oxymatrine in rats was increased remarkably after oral administration of OMT-PLC (p<0.05), compared with those of oxymatrine or the physical mixture. This was mainly due to an improvement of the solubility of OMT-PLC.


Asunto(s)
Alcaloides/farmacocinética , Antivirales/farmacocinética , Fosfolípidos/química , Quinolizinas/farmacocinética , Administración Oral , Alcaloides/administración & dosificación , Animales , Antivirales/administración & dosificación , Área Bajo la Curva , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría , Química Farmacéutica/métodos , Portadores de Fármacos/química , Hepatocitos/metabolismo , Modelos Lineales , Masculino , Permeabilidad , Quinolizinas/administración & dosificación , Ratas , Solubilidad , Factores de Tiempo , Difracción de Rayos X
15.
Artículo en Inglés | MEDLINE | ID: mdl-19406710

RESUMEN

We discuss the feasibility of surface acoustic wave (SAW) radio-frequency identification (RFID) tags that rely on ultra-wideband (UWB) technology. We propose a design of a UWB SAW tag, carry out numerical experiments on the device performance, and study signal processing in the system. We also present experimental results for the proposed device and estimate the potentially achievable reading distance. UWB SAW tags will have an extremely small chip size (<0.5 x 1 mm(2)) and a low cost. They also can provide a large number of different codes. The estimated read range for UWB SAW tags is about 2 m with a reader radiating as low as <0.1 mW power levels with an extremely low duty factor.


Asunto(s)
Sistemas Microelectromecánicos/instrumentación , Etiquetado de Productos/instrumentación , Etiquetado de Productos/normas , Estudios de Factibilidad , Regulación Gubernamental , Guías como Asunto , Microondas
16.
Biomed Chromatogr ; 22(10): 1084-90, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18506728

RESUMEN

A reversed-phase high-performance liquid chromatographic method with diode array detection was established to simultaneously determine the seven bioactive lignans in Herpetospermum caudigerum, namely ent-isolariciresinol (1), dehydrodiconiferyl alcohol (2), herpetrione (3), herpetin (4), herpetetrone (5), herpetotriol (6) amd herpetal (7). The HPLC assay was performed on a Restek Pinnacle DB C18 column (250 x 4.6 mm, 5 microm) with gradient elution of acetonitrile and 0.1% phosphoric acid within 65 min. The detection wavelength was 240 nm. The flow-rate was 1.0 mL/min. All calibration curves showed good linearity (r2 > 0.9998) within test ranges. The method was reproducible with intra- and inter-day variation of less than 1.98%. The method provided good accuracy with recoveries in the range 95.19-102.64% with RSDs less than 1.52%. The method was successfully applied to the quantification of seven constituents in 15 H. caudigerum samples collected from different cities. The results indicated that the developed assay could be considered as a suitable quality control method for H. caudigerum.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cucurbitaceae/química , Lignanos/análisis , Estabilidad de Medicamentos , Reproducibilidad de los Resultados
17.
Chem Pharm Bull (Tokyo) ; 55(11): 1563-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17978512

RESUMEN

To decrease the hemolysis side effect of puerarin, a novel approach of Complex-Phase Inversion-Homogenization (CPIH) Technology was established to prepare intravenous puerarin emulsions. Preparation of puerarin submicron emulsion were optimized by central composite design, and the physicochemical properties were evaluated. Puerarin phospholipid complexs prepared by puerarin and phospholipids at a ratio of 1 : 1.2. In order to improve the product quality, a central composite design was applied to optimize the critical process variables, such as emulsification time, stirring velocity and homogenization press, and the results were modeled statistically. Puerarin phospholipid complexs prepared were identified by fourier transform infrared spectrophotometry. The datas showed that the parameters had great effect on the response values. The particle size, span of dispersity and entrapment efficiency of puerarin emulsions prepared using the optimal parameters settings were 218.23 nm, 0.6284 and 87.32%, respectively. These meant that over 87% of the drug was located at the surfactant interface and oil droplet, the concentration of puerarin in aqueous was rarely. And the puerarin emulsion prepared by CPIH technology were sufficient stable for 90 d. The CPIH technology can be used as a general formulation principle for drugs which are slightly soluble in water and poorly soluble in oils.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Emulsionantes/química , Isoflavonas/química , Fosfolípidos/química , Solventes/química , Vasodilatadores/química , Emulsionantes/administración & dosificación , Emulsionantes/farmacocinética , Inyecciones Intravenosas , Isoflavonas/administración & dosificación , Isoflavonas/farmacocinética , Microscopía Electrónica de Transmisión , Aceites , Tamaño de la Partícula , Fosfolípidos/administración & dosificación , Fosfolípidos/farmacocinética , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Vasodilatadores/administración & dosificación , Vasodilatadores/farmacocinética , Agua/química
18.
Chem Pharm Bull (Tokyo) ; 54(11): 1592-4, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17077559

RESUMEN

From the ethanol extract of the seeds of Herpetospermum caudigerum wall, one new lignan compound 1, was isolated and characterized along with three known compounds 2, 3 and 4. The structure elucidation of the isolated new compound was performed on the basis of spectroscopic and chemical evidence. The structures of known compounds were determined by comparison of spectral data and physical data with those previously reported. The activity inhibiting hepatitis b virus was evaluated. Preliminary studies showed that compound 1 and 2 displayed promising inhibitory potential against hepatitis b virus.


Asunto(s)
Antivirales/farmacología , Cucurbitaceae/química , Virus de la Hepatitis B/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales/química , Antivirales/química , Antivirales/aislamiento & purificación , Línea Celular Tumoral , ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Ligandos , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Semillas/química , Especificidad de la Especie , Estereoisomerismo , Factores de Tiempo , Células Tumorales Cultivadas
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