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1.
Food Chem ; 310: 125819, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31732248

RESUMO

The well-known red color change plays a significant role in consumer acceptability of crustacean species. In this study, we described the purification of the red color-related protein named MjRCP75 from the shell of Marsupenaeus japonicus. It was a homogeneous monomer with molecular mass of 75 kDa and rich in α-helix conformation. The α-helix content decreased within the increasing of heating temperature and was transformed dominantly to ß types. Identification and structural analysis revealed that MjRCP75 belonged to hemocyanin family. The released pigment from heated MjRCP75 showed a λmax at 483 nm in acetone. MjRCP75 showed clearly antibacterial activity against Escherichia coli, Staphylococcus aureus, and Vibrio parahaemolyticus. These findings identify MjRCP75 as the red color-related protein in M. japonicus shell and reveal its involvement in antibacterial activities.

2.
Foods ; 8(12)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775386

RESUMO

A two-stage simulated gastro-intestinal (GI) digestion model (2 h pepsin treatment and subsequent 2 h pancreatin treatment at 37 °C) was used to explore the antioxidant activity of the digested products of Cyprinus carpio haematopterus scale gelatin with different molecular weights (MW). From the gastric phase to the intestinal phase, the hydrolysis degree of the products increased from 2.6 ± 0.4% to 16.9 ± 0.7%. The fraction of 0-1 kDa (JCP3) exhibited the best antioxidant activities in hydroxyl radical scavenging, reducing power, and metal chelating activity. The fraction of 1-3 kDa (JCP2) exhibited the best 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. However, the fractions of 0-1 kDa (JCP3) and 1-3 kDa (JCP2) showed similar inhibitory activity of lipid peroxidation. The results indicated that Cyprinus carpio haematopterus scale gelatin can be digested in the gastrointestinal tract. Furthermore, the digested products had antioxidant activity.

3.
Molecules ; 24(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430953

RESUMO

Schizochytrium limacinum residue was hydrolyzed with various proteases (papain, trypsin, Flavourzyme, Protamex, and Alcalase 2.4L) to obtain antioxidative peptides. The results showed that the S. limacinum hydrolysates (SLHs) prepared with compound proteases (Protamex and Alcalase 2.4L) had the highest antioxidant activity, which was measured using methods such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability (IC50 = 1.28 mg/mL), hydroxyl radical scavenging ability (IC50 = 1.66 mg/mL), and reducing power (1.42 at 5.0 mg/mL). The hydrolysates were isolated and purified by ultrafiltration, gel filtration chromatography, and reverse-phase high-performance liquid chromatography (RP-HPLC). Through analysis of electrospray ionization-mass spectrometer (ESI-MS/MS), the purified antioxidant peptide was identified as Pro-Tyr-Lys (406 Da). Finally, the identified peptide was synthesized for evaluating its antioxidant activity. The •OH scavenging ability and reducing power of Pro-Tyr-Lys were comparable to those of reduced L-glutathione (GSH). These results demonstrated that the antioxidant peptides from SLHs could potentially be used as effective antioxidants.


Assuntos
Antioxidantes/química , Microalgas/química , Peptídeos/química , Hidrolisados de Proteína/química , Compostos de Bifenilo/química , Depuradores de Radicais Livres/química , Glutationa/química , Hidrólise , Radical Hidroxila/química , Peroxidação de Lipídeos , Peptídeo Hidrolases/química , Picratos/química , Espectrometria de Massas por Ionização por Electrospray , Superóxidos/química
4.
J Sci Food Agric ; 99(14): 6121-6128, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31260117

RESUMO

Shrimp has been widely accepted as an excellent resource for white meat due to its high-protein and low-fat content, especially low cholesterol. However, shrimps are highly perishable during preservation and retailing procedures due to the activities of enzymatic proteolysis, lipid oxidation, and microbial degradation. With increasing knowledge of and demands for safety, nutrition, and freshness of shrimp products, energy efficient, quality, maintained, and sustainable preservation technologies are needed. Low-temperature preservation, a practical processing method for improving the shelf life of food products, is widely used in the aquatic industry. This review focuses on the effects of low-temperature preservation on the quality changes in Litopenaeus vannamei. It considers physicochemical properties, sensory evaluation, melanosis assessment, and microbiological analysis. The perspectives of non-protein-based techniques on quality analysis of shrimps during preservation are also discussed. © 2019 Society of Chemical Industry.


Assuntos
Penaeidae/química , Frutos do Mar/análise , Animais , Conservação de Alimentos , Controle de Qualidade , Temperatura Ambiente
5.
Food Chem ; 296: 132-141, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31202297

RESUMO

Spontaneous fermentation is a critical step in the processing of high-quality fish sauce. In this study, a comparative UHPLC-Q/TOF-MS-based metabolomics approach combining equivalent-quantification and the taste activity value (TAV) was used, for the first time, to evaluate the taste qualities and characterize metabolite profiles in Chinese fish sauce during fermentation. A total of 22,816 metabolite ion features were extracted from fish sauce samples. Forty-six metabolites, including amino acids, small peptides, organic acids, amines, carbohydrates, and nucleic acids, were identified as key chemical components of fish sauce. In addition, absolute quantification and TAV showed that aspartic acid and glutamic acid exert an important influence on the umami taste of fish sauce. Specific metabolites were primarily associated with amino acid metabolism, particularly alterations in arginine and proline metabolism. This study identifies chemical components and provides novel insights into the taste quality of fish sauce due to fermentation.


Assuntos
/análise , Peixes/metabolismo , Metabolômica/métodos , Paladar , Aminoácidos/análise , Animais , China , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Análise dos Mínimos Quadrados , Espectrometria de Massas , Análise de Componente Principal
6.
J Pharm Biomed Anal ; 169: 1-10, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30826486

RESUMO

There is an increasing focus on the quality consistency evaluation of dispensing granule in traditional Chinese medicines (TCMs). According to the guideline from Chinese Pharmacopoeia Commission, the substantial equivalence of dispensing granule and traditional decoction should be determined, and the chromatographic fingerprint has been recommended as a comprehensive qualitative approach to assess the quality consistency between dispensing granule and traditional decoction. However, a high-degree chemical similarity does not equal a bioequivalence. Attempting to realize the quality evaluation by integrating chemical consistency and bioequivalence, we herein proposed a totality-of-the-evidence approach based on clustering analysis and equivalence evaluation taking the dispensing granule and traditional decoction of Scutellariae Radix (SR) as a typical case. Chemical fingerprints were developed by high performance liquid chromatography coupled with photodiode array detector and quadrupole time-of-flight mass spectrometry (HPLC-PDA/QTOF-MS). Subsequently, a feature selection strategy, integrated linear and nonlinear correlation analysis, was carried out to assess the correlation between chemical profiles and biological activities. Finally, quality consistency between the dispensing granule and the traditional decoction was determined by bioactive marker-guided hierarchical clustering analysis (HCA), k-means clustering method and bioequivalence evaluation. The available evidence suggested that not all the dispensing granule of SR were sufficiently similar to the traditional decoction. This study provides an applicable methodology for quality consistency evaluation of dispensing granule and traditional decoction in TCMs.


Assuntos
Medicamentos de Ervas Chinesas/química , Scutellaria baicalensis/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Medicina Tradicional Chinesa/métodos , Projetos Piloto , Equivalência Terapêutica
7.
Food Funct ; 9(8): 4135-4142, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30019729

RESUMO

In this study, with grass fish bones as the substrate, after flavourzyme treatment, and fermentation with Leuconostoc mesenteroides, a fermentation solution with a high content of soluble calcium was obtained. High performance liquid chromatography and GC-MS analysis indicated that free calcium (11.29 mmol L-1) in the fermentation solution was composed of calcium lactate (3.89 mmol L-1), calcium acetate (6.21 mmol L-1), calcium amino acids and small peptide calcium. Animal experiments show that the fermentation solution of grass fish bones could promote the growth and development of calcium-deficient rats. Complex organic calcium could be well absorbed and utilized by rats so that serum calcium, alkaline phosphatase levels, femur weight and other indicators in calcium-deficient rats could be returned to normal levels. The fermentation solution of grass fish bones can avoid the waste of aquatic proteins and fish bone calcium, and it exhibited high calcium bioavailability. Therefore, the fermentation solution of grass fish bones might be used as a new efficient calcium supplement.


Assuntos
Osso e Ossos/química , Cálcio/farmacocinética , Carpas , Fosfatase Alcalina , Ração Animal/análise , Animais , Densidade Óssea , Cálcio/administração & dosagem , Cálcio/sangue , Cálcio/química , Dieta/veterinária , Fermentação , Manipulação de Alimentos , Leuconostoc mesenteroides/fisiologia , Masculino , Fósforo/sangue , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
8.
Artigo em Chinês | MEDLINE | ID: mdl-27356418

RESUMO

OBJECTIVE: To evaluate the effect of schistosomiasis control in Yizhou City, Guangxi Zhuang Autonomous Region, from 2011 to 2014, so as to provide the evidence for formulating the further prevention and control strategy. METHODS: The schistosomiasis surveillance data were collected and analyzed in Yizhou City from 2011 to 2014. RESULTS: From 2011 to 2014, 770.38 hm² was surveyed for the Oncomelania hupensis snails, and two snail infested sites were found, while no infected snails were found. Totally 3,524 residents were tested by ELISA for Schistosoma japonicum infection, and 38 cases were positive. The positive rate of 2013 was significantly higher than those of other three years (χ² = 15.08, P < 0.05). Totally 432 rats and 28 dogs were dissected and 1,697 cattle were examined by the stool test, but no positive cases were found. CONCLUSIONS: The indicators of schistosomiasis surveillance are basically stable in Yizhou City.


Assuntos
Esquistossomose/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , China/epidemiologia , Doenças Endêmicas , Humanos , Pessoa de Meia-Idade , Esquistossomose/prevenção & controle , Caramujos , Fatores de Tempo
9.
Robotics Biomim ; 3: 1, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27054060

RESUMO

For a biped climbing robot with dual grippers to climb poles, trusses or trees, feasible collision-free climbing motion is inevitable and essential. In this paper, we utilize the sampling-based algorithm, Bi-RRT, to plan single-step collision-free motion for biped climbing robots in spatial trusses. To deal with the orientation limit of a 5-DoF biped climbing robot, a new state representation along with corresponding operations including sampling, metric calculation and interpolation is presented. A simple but effective model of a biped climbing robot in trusses is proposed, through which the motion planning of one climbing cycle is transformed to that of a manipulator. In addition, the pre- and post-processes are introduced to expedite the convergence of the Bi-RRT algorithm and to ensure the safe motion of the climbing robot near poles as well. The piecewise linear paths are smoothed by utilizing cubic B-spline curve fitting. The effectiveness and efficiency of the presented Bi-RRT algorithm for climbing motion planning are verified by simulations.

10.
J Sci Food Agric ; 96(10): 3374-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26526607

RESUMO

BACKGROUND: Lipid oxidation can occur in fish fillets during long-term frozen storage and cause quality and nutrition loss, which is a major concern in the seafood industry. Our previous study showed that chitosan combined with citric acid or licorice extract can have a preserving effect on fresh fish fillets stored at 4 °C. It is of interest to further study their antioxidant effects on fish fillets during frozen storage. RESULTS: Chitosan, chitosan and citric acid, chitosan and licorice extract can inhibit primary and secondary lipid oxidation, as indicated by lower peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) values compared to the control samples. In addition, drip loss was decreased in the treatment samples. Both citric acid and licorice extract enhanced the antioxidant effects of chitosan. Among all the three treatments, chitosan and licorice extract showed the best antioxidant effects, reducing both PV and TBARS significantly at the end of storage. CONCLUSION: The combination of chitosan and citric acid or licorice extract showed significant antioxidant effects on ovate pompano fillets at -18 °C during 6 months of storage. They could be applied as natural antioxidant preservatives for use in seafood products or other meat products. © 2015 Society of Chemical Industry.


Assuntos
Quitosana/farmacologia , Ácido Cítrico/farmacologia , Armazenamento de Alimentos/métodos , Glycyrrhiza/química , Peroxidação de Lipídeos/efeitos dos fármacos , Perciformes , Alimentos Marinhos , Animais , Antioxidantes/farmacologia , Conservação de Alimentos/métodos , Extratos Vegetais/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise
11.
Food Funct ; 6(6): 1919-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25965854

RESUMO

Recently, much attention has been given to improving the antioxidant activity of protein hydrolysates via the Maillard reaction, but little is known about the cellular antioxidant activity of Maillard reaction products (MRPs) from protein hydrolysates. We first investigated chemical characterization and the cellular antioxidant activity of MRPs in a shrimp (Litopenaeus vannamei) by-product protein hydrolysate (SBH)-glucose system at 110 °C for up to 10 h of heating. Solutions of SBH and glucose were also heated alone as controls. The Maillard reaction greatly resulted in the increase of hydroxymethylfurfural (HMF) and browning intensity, high molecular weight fraction, and reduction of the total amino acid in SBH with the heating time, which correlated well with the free radical scavenging activity of MRPs. MRPs had stronger inhibiting effects on oxidative stress of human HepG2 cells than the original SBH, and its cellular antioxidant activity strongly correlated with free radical scavenging activity, but less affected by the browning intensity and HMF level. The caramelization of glucose partially affected the HMF level and free radical scavenging activity of MRPs, but it was not related to the cellular antioxidant activity. The cellular antioxidant activity of MRPs for 5 h of heating time appeared to reach a maximum level, which was mainly due to carbonyl ammonia condensation reaction. In conclusion, the Maillard reaction is a potential method to increase the cellular antioxidant activity of a shrimp by-product protein hydrolysate, but the higher HMF levels and the lower amino acid content in MRPs should also be considered.


Assuntos
Antioxidantes/química , Proteínas de Artrópodes/química , Hepatócitos/metabolismo , Estresse Oxidativo , Penaeidae/química , Hidrolisados de Proteína/química , Espécies Reativas de Oxigênio/antagonistas & inibidores , Animais , Antioxidantes/economia , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Proteínas de Artrópodes/economia , Proteínas de Artrópodes/isolamento & purificação , Proteínas de Artrópodes/metabolismo , Sobrevivência Celular , China , Proteínas na Dieta/química , Proteínas na Dieta/economia , Proteínas na Dieta/isolamento & purificação , Proteínas na Dieta/metabolismo , Suplementos Nutricionais/análise , Suplementos Nutricionais/economia , Conservantes de Alimentos/química , Conservantes de Alimentos/economia , Conservantes de Alimentos/isolamento & purificação , Conservantes de Alimentos/metabolismo , Indústria de Processamento de Alimentos/economia , Furaldeído/análogos & derivados , Furaldeído/análise , Furaldeído/química , Glucose/química , Células Hep G2 , Temperatura Alta , Humanos , Resíduos Industriais/análise , Resíduos Industriais/economia , Reação de Maillard , Peso Molecular , Hidrolisados de Proteína/economia , Espécies Reativas de Oxigênio/metabolismo
12.
Food Chem ; 162: 156-60, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24874371

RESUMO

The preserving effects of chitosan, chitosan and citric acid, chitosan and licorice extract on fresh Japanese sea bass fillets stored at 4 °C for 12 days were studied. Results showed that citric acid or licorice extract can enhance the preserving function of chitosan significantly by retarding lipid oxidation and inhibiting microbial growth as reflected in thiobarbituric acid reactive substances and total plate count, respectively. Both total volatile basic nitrogen values and sensory scores indicated chitosan and citric acid or licorice extract can significantly reduce the quality loss and extend the shelf life of Japanese sea bass fish fillets during refrigerated storage. Citric acid or licorice extract with chitosan could thus be applied in the seafood industry to enhance quality of fish fillets as natural preservatives.


Assuntos
Ácido Cítrico/química , Animais , Bass , Peixes , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Glycyrrhiza , Japão , Alimentos Marinhos/análise
13.
Yao Xue Xue Bao ; 47(10): 1384-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23289153

RESUMO

A new mathematical equation characterizing the compression of pharmaceutical materials is presented. This equation presumed that the rate of change of the compressible volume of powder with respect to the pressure is proportional to the compressible volume. The new model provided a good fit to several model substances employing non-linear regression techniques. The validity of the model had been verified with experimental results of various pharmaceutical powders according to the Akaikes informatics criterion (AIC) and the sum of squared deviations (SS). The parameter of the new model might reflect quantitatively the fundamental compression behaviors of the powders. It had demonstrated that the proposed model could well predict the compaction characteristics of solid particles like the Kawakita model.


Assuntos
Força Compressiva , Dinâmica não Linear , Pós/química , Pressão
14.
Yao Xue Xue Bao ; 44(4): 412-6, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19545061

RESUMO

Microcrystalline cellulose (MCC), calcium phosphate (DCP)/MCC (4:1, w/w) and lactose (Lac)/MCC (4:1) pellets with different intragranular porosity were prepared in an extrusion-spheronizator and three volume ratios of ethanol/water were used as binder agents to prepare pellets. The compression behaviors of these pellets with different intragranular pore volume were evaluated with the parameters of Kawakita model. The results showed that high pore volume of pellets made up of MCC had the best compressibility and low pore volume of pellets had a poor compactibility. However, the compressibility of different porosity of pellets made up of DCP/MCC (4:1) or Lac/MCC (4:1) was good, but they were not significantly different. The reason might be the main compression mechanism of high porosity of MCC pellets was plastic deformation and that of DCP/MCC pellets or Lac/MCC pellets was not plastic deformation but fragmentation. These results can be observed directly by the SEM photographs. According to these results, the conclusion could be drawn that high porosity MCC pellets and different porosity DCP/MCC pellets and Lac/MCC pellets can be used as cushion granules to maintain the original shape and release characteristics of drug pellets when pellets were tabletted.


Assuntos
Fosfatos de Cálcio/química , Celulose/química , Composição de Medicamentos/métodos , Lactose/química , Comprimidos , Excipientes , Microesferas , Porosidade , Pressão
15.
Yao Xue Xue Bao ; 43(1): 97-101, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18357741

RESUMO

Fluidized-bed manufactured enteric-coated diclofenac sodium pellets were compressed into tablets. The blend of two aqueous acrylic resins dispersion in different ratios, Eudragit NE30D and Eudragit L30D-55, were used to prepare enteric-coated diclofenac sodium pellets of different particle sizes and coating level. The cushioning pellets with different properties and these enteric-coated pellets were compressed into tablets in different proportions. The drug release of the tablets containing these pellets would be lower than 10% in 2 h in simulated gastric fluid, but reach (83 +/- 2.42)% in 1 h in simulated enteric fluid. The mixture of Eudragit NE30D and Eudragit L30D-55 could be used to prepare enteric pellets which are suitable for compression. The cushioning pellets which were composed of stearic acid/microcrystalline cellulose (4:1, w/w) could avoid rupture of the coating of pellets during the compression.


Assuntos
Resinas Acrílicas/química , Anti-Inflamatórios não Esteroides/síntese química , Diclofenaco/síntese química , Sistemas de Liberação de Medicamentos , Comprimidos com Revestimento Entérico/química , Celulose/química , Portadores de Fármacos , Composição de Medicamentos/métodos , Metacrilatos/química , Tamanho da Partícula , Polímeros/química , Solubilidade
16.
Drug Dev Ind Pharm ; 33(8): 888-99, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17729107

RESUMO

Solid dispersions (SDs) of dipyridamole (DIP) with a novel carrier copolyvidonum Plasdone S-630 (CoPVP) were developed by solvent evaporation method. The solid state of SDs of DIP with CoPVP (SDs CoPVP) was characterized by fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and polarizing microscopy, compared with that of SDs of DIP with polyvinylpyrrolidone Plasdone K-29/32 (SDs PVP). FT-IR analysis demonstrated the presence of intermolecular hydrogen bonding between DIP and CoPVP or PVP in SDs. DSC and XRD studies indicated that DIP presented in amorphous state in both SDs CoPVP and SDs PVP at higher weight ratios. The dissolution property of SDs CoPVP was significantly improved in comparison of pure DIP and physical mixtures with CoPVP (PM CoPVP). Both SDs CoPVP and SDs PVP powder showed the favorable flowability. However, SDs CoPVP showed better compressibility than SDs PVP. The lower hydroscopicity of SDs CoPVP could be advantageous to the stability to SDs. This study proves the potential of CoPVP as a carrier in the formulations of SDs for poorly soluble drugs.


Assuntos
Acetatos , Dipiridamol/química , Inibidores da Agregação de Plaquetas/química , Povidona/análogos & derivados , Varredura Diferencial de Calorimetria , Dipiridamol/administração & dosagem , Portadores de Fármacos , Microscopia de Polarização , Inibidores da Agregação de Plaquetas/administração & dosagem , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Pharmazie ; 62(12): 907-13, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18214341

RESUMO

A combined delivery system, containing two kinds of diltiazem hydrochloride multi-layer coated pellets with different release characteristics, was developed to meet chronotherapeutic requirements. The dissolution studies in vitro indicated that the combined system could constantly release drug at a predetermined time in synchrony with the biologic rhythm of disease activity. These two kinds of pellets were mixed at the ratio 1:1. Pellet 2 could provide drug during the later phase of drug release from pellet 1, because the amount released was insufficient in the later phase (about 14-24 h after administration) for pellet 1. Addition of Tween 20 in the HPMC swelling layer was able to modify the hydration rate of HPMC layer which controlled the delayed time of the release system. It was found that the drug release kinetics followed Hixson-Crowell equation and this indicated that the main drug-transport mechanism inside the pellets was an erosion mechanism. The drug release rate was independent of the hydrodynamic conditions and pH of the external environment, and showed a decrease with increasing of osmotic pressure of the dissolution medium. These release characteristics indicated that the drug release from this system was driven by osmotic-pressure gradient.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Diltiazem/administração & dosagem , Bloqueadores dos Canais de Cálcio/química , Preparações de Ação Retardada , Diltiazem/química , Composição de Medicamentos , Excipientes , Concentração de Íons de Hidrogênio , Derivados da Hipromelose , Cinética , Modelos Lineares , Metilcelulose/análogos & derivados , Microscopia Eletrônica de Varredura , Microesferas , Modelos Químicos , Pressão Osmótica , Tamanho da Partícula , Polissorbatos , Solubilidade
18.
Zhongguo Zhen Jiu ; 26(7): 507-9, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16903605

RESUMO

OBJECTIVE: To investigate the correlation of skin electric resistance changes with the blood drug content in acupoint transdermal administration, and to establish an new evaluation index for drug delivery efficiency through acupoints. METHODS: Twenty-four rabbits were randomly divided into an observation group and a control group. In the observation group, aminophylline was administrated through "Feishu" (BL 13), "Geshu" (BL 17) and "Danzhong" (CV 17) which are commonly used for treatment of bronchial asthma, and the control group through sham-points on the back. The skin resistance and plasma aminophylline content were determined after application of aminophylline to the points, and their changes with time were observed. The ratio of Css/Rss at stability was defined as delivery coefficient (DC) which reflects the efficiency of delivering drug at acupoints and sham acupoints. RESULTS: Both the plasma aminophylline and the skin resistance value tended to steady about 6-8 h after application of aminophyiophylline. The DC in the acupoints was higher than that in the sham-acupoints (P < 0.01). And there was significant difference as DC of the "Feishu"was significant difference (BL 13) and "Danzhongas DC of the "Feish" (BLCV 17) compared with that of "Geshu" (BL 17) (P < 0.01). CONCLUSION: The bigger the DC is, the higher the efficiency of drug delivery is; the efficiency of drug delivery through acupoints is higher than that through sham-acupoints.


Assuntos
Pontos de Acupuntura , Aminofilina/administração & dosagem , Aminofilina/farmacocinética , Administração Cutânea , Animais , Impedância Elétrica , Feminino , Masculino , Coelhos
19.
Yao Xue Xue Bao ; 40(7): 606-10, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16196265

RESUMO

AIM: To prepare the combined system of diltiazem hydrochloride delayed-onset sustained-release pellets in order to make time-specific drug delivery system. The drug can release from the system sustained after a predetermined lag time, and the release behavior can continue till 24 hour after administrating the formulation. According to the concept of chronotherapy, the combined system is useful to improve the pharmacotherapy of cardiovascular diseases. METHODS: The velocity-time curve of the drug release from the multiple-unit system containing pellets was consistent with the fluctuation curve following time of blood pressure and heart ratio. So the velocity-time curve was selected to describe the release behavior of the combined system. The velocity-time equation describing the release behavior of two kinds of pellets was deduced by non-linear least square model fit. And zero-order kinetics equation was adopted to fit the release behavior of different combinations which were composed of different proportion of two kinds of pellets. The velocity-time equation describing the release behavior of the combinations was deduced by non-linear least square model fit, too. The difference of combinations in velocity-time curves between theoretical value and test value was compared. RESULTS: The results showed that the test values were closely approximate to the theoretical values. Therefore, the multiple unit drug delivery system can be described by adding the velocity-time equations of different pellets to calculate the theoretical equations. CONCLUSION: A multiple-unit combined system containing different coated pellets, as a novel delayed-onset sustained-release system, was prepared. Then a time-specific drug delivery system has been made. The programmed drug delivery system could be predicted by adding the velocity-time equation of each kind of pellets to calculate the theoretical equations. characterized by mathematics equation. The release behavior of pellets system could be characterized by mathematics equation.


Assuntos
Diltiazem/administração & dosagem , Sistemas de Liberação de Medicamentos , Cápsulas , Preparações de Ação Retardada , Matemática , Modelos Químicos , Tecnologia Farmacêutica/métodos
20.
Yao Xue Xue Bao ; 39(6): 472-6, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15491109

RESUMO

AIM: To prepare nifedipine (NP) rapid release mini-tablet, sustained release mini-tablets, pulsed release mini-tablets and delayed-onset sustained release mini-tablets and develop multiplied pulsed drug delivery system (DDS), site-specific DDS, zero-order DDS and quick/slow DDS by various ways. METHODS: Velocity-time (v-t) equation of each mini-tablet was deduced by non-linear least square model fit. The difference of combinations in v-t profiles between theoretical value and test value was compared. RESULTS: According to the v-t equations, the combined release behaviors were observed directly from v-t profiles and the test values coincided with the theoretical profiles. CONCLUSION: The programmed DDS, which consist of a variety of mini-tablets with different dosages and combinations in capsules, could be predicted by summing up the v-t equation of each tablet.


Assuntos
Sistemas de Liberação de Medicamentos , Nifedipino/administração & dosagem , Povidona/análogos & derivados , Cápsulas , Preparações de Ação Retardada , Modelos Químicos , Nifedipino/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Povidona/administração & dosagem , Povidona/química , Solubilidade , Amido/química , Comprimidos
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