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1.
Med Phys ; 51(1): 18-30, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37856190

RESUMEN

BACKGROUND: Online adaptive radiotherapy (ART) involves the development of adaptable treatment plans that consider patient anatomical data obtained right prior to treatment administration, facilitated by cone-beam computed tomography guided adaptive radiotherapy (CTgART) and magnetic resonance image-guided adaptive radiotherapy (MRgART). To ensure accuracy of these adaptive plans, it is crucial to conduct calculation-based checks and independent verification of volumetric dose distribution, as measurement-based checks are not practical within online workflows. However, the absence of comprehensive, efficient, and highly integrated commercial software for secondary dose verification can impede the time-sensitive nature of online ART procedures. PURPOSE: The main aim of this study is to introduce an efficient online quality assurance (QA) platform for online ART, and subsequently evaluate it on Ethos and Unity treatment delivery systems in our clinic. METHODS: To enhance efficiency and ensure compliance with safety standards in online ART, ART2Dose, a secondary dose verification software, has been developed and integrated into our online QA workflow. This implementation spans all online ART treatments at our institution. The ART2Dose infrastructure comprises four key components: an SQLite database, a dose calculation server, a report generator, and a web portal. Through this infrastructure, file transfer, dose calculation, report generation, and report approval/archival are seamlessly managed, minimizing the need for user input when exporting RT DICOM files and approving the generated QA report. ART2Dose was compared with Mobius3D in pre-clinical evaluations on secondary dose verification for 40 adaptive plans. Additionally, a retrospective investigation was conducted utilizing 1302 CTgART fractions from ten treatment sites and 1278 MRgART fractions from seven treatment sites to evaluate the practical accuracy and efficiency of ART2Dose in routine clinical use. RESULTS: With dedicated infrastructure and an integrated workflow, ART2Dose achieved gamma passing rates that were comparable to or higher than those of Mobius3D. Additionally, it significantly reduced the time required to complete pre-treatment checks by 3-4 min for each plan. In the retrospective analysis of clinical CTgART and MRgART fractions, ART2Dose demonstrated average gamma passing rates of 99.61 ± 0.83% and 97.75 ± 2.54%, respectively, using the 3%/2 mm criteria for region greater than 10% of prescription dose. The average calculation times for CTgART and MRgART were approximately 1 and 2 min, respectively. CONCLUSION: Overall, the streamlined implementation of ART2Dose notably enhances the online ART workflow, offering reliable and efficient online QA while reducing time pressure in the clinic and minimizing labor-intensive work.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Humanos , Planificación de la Radioterapia Asistida por Computador/métodos , Estudios Retrospectivos , Programas Informáticos , Radioterapia de Intensidad Modulada/métodos , Tomografía Computarizada por Rayos X , Dosificación Radioterapéutica
3.
Biomed Res Int ; 2017: 3923865, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28337449

RESUMEN

The current use of a single chemical component as the representative quality control marker of herbal food supplement is inadequate. In this CD80-Quantitative-Pattern-Activity-Relationship (QPAR) study, we built a bioactivity predictive model that can be applicable for complex mixtures. Through integrating the chemical fingerprinting profiles of the immunomodulating herb Radix Astragali (RA) extracts, and their related biological data of immunological marker CD80 expression on dendritic cells, a chemometric model using the Elastic Net Partial Least Square (EN-PLS) algorithm was established. The EN-PLS algorithm increased the biological predictive capability with lower value of RMSEP (11.66) and higher values of Rp2 (0.55) when compared to the standard PLS model. This CD80-QPAR platform provides a useful predictive model for unknown RA extract's bioactivities using the chemical fingerprint inputs. Furthermore, this bioactivity prediction platform facilitates identification of key bioactivity-related chemical components within complex mixtures for future drug discovery and understanding of the batch-to-batch consistency for quality clinical trials.


Asunto(s)
Antígeno B7-1/biosíntesis , Medicamentos Herbarios Chinos/administración & dosificación , Factores Inmunológicos/administración & dosificación , Extractos Vegetales/administración & dosificación , Astragalus propinquus , Antígeno B7-1/química , Línea Celular , Células Dendríticas/efectos de los fármacos , Descubrimiento de Drogas , Medicamentos Herbarios Chinos/química , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Factores Inmunológicos/química , Extractos Vegetales/química , Relación Estructura-Actividad Cuantitativa
4.
J Anal Methods Chem ; 2017: 9402045, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28168083

RESUMEN

The rapid increase in the use of metabolite profiling/fingerprinting techniques to resolve complicated issues in metabolomics has stimulated demand for data processing techniques, such as alignment, to extract detailed information. In this study, a new and automated method was developed to correct the retention time shift of high-dimensional and high-throughput data sets. Information from the target chromatographic profiles was used to determine the standard profile as a reference for alignment. A novel, piecewise data partition strategy was applied for the determination of the target components in the standard profile as markers for alignment. An automated target search (ATS) method was proposed to find the exact retention times of the selected targets in other profiles for alignment. The linear interpolation technique (LIT) was employed to align the profiles prior to pattern recognition, comprehensive comparison analysis, and other data processing steps. In total, 94 metabolite profiles of ginseng were studied, including the most volatile secondary metabolites. The method used in this article could be an essential step in the extraction of information from high-throughput data acquired in the study of systems biology, metabolomics, and biomarker discovery.

5.
Anal Chim Acta ; 870: 45-55, 2015 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-25819786

RESUMEN

Bioactive component identification is a crucial issue in search for new drug leads. We provide a new strategy to search for bioactive components based on Sure Independence Screening (SIS) and interval PLS (iPLS). The method, which is termed as SIS-iPLS, is not only able to find out the chief bioactive components, but also able to judge how many components should be there responsible for the total bioactivity. The method is totally "data-driven" with no need for prior knowledge about the unknown mixture analyzed, therefore especially suitable for effect-directed work like bioassay-guided fractionation. Two data sets, a synthetic mixture system of twelve components and a suite of Radix Puerariae Lobatae extracts samples, are used to test the identification ability of the SIS-iPLS method.


Asunto(s)
Productos Biológicos/análisis , Productos Biológicos/farmacología , Cromatografía/métodos , Métodos Analíticos de la Preparación de la Muestra , Antioxidantes/análisis , Antioxidantes/farmacología , Bioensayo , Hierro/química , Análisis de los Mínimos Cuadrados , Oxidación-Reducción/efectos de los fármacos , Pueraria/química , Reproducibilidad de los Resultados
6.
J Chem Phys ; 140(19): 194311, 2014 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-24852542

RESUMEN

We have computed the potential energy surfaces of the X¹A' and ùA" states of HPS using the explicitly correlated multi-reference configuration interaction (MRCI-F12) method, and Franck-Condon factors between the two states, which include anharmonicity and Duschinsky rotation, with the aim of testing the assignment of the recently reported single-vibronic-level (SVL) emission spectrum of HPS [R. Grimminger, D. J. Clouthier, R. Tarroni, Z. Wang, and T. J. Sears, J. Chem. Phys. 139, 174306 (2013)]. These are the highest level calculations on these states yet reported. It is concluded that our spectral simulation supports the assignments of the molecular carrier, the electronic states involved and the vibrational structure of the experimental laser induced fluorescence, and SVL emission spectra proposed by Grimminger et al. [J. Chem. Phys. 139, 174306 (2013)]. However, there remain questions unanswered regarding the relative electronic energies of the two states and the geometry of the excited state of HPS.

7.
J Chem Phys ; 139(1): 014301, 2013 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-23822297

RESUMEN

We have carried out high-level ab initio calculations on AlH2 and its anion, as well as Franck-Condon factor calculations, which include anharmonicity and Duschinsky rotation, to simulate the photodetachment spectrum of AlH2(-), with the aim of assigning the very recently reported photodetachment spectrum of AlH2(-) [X. Zhang, H. Wang, E. Collins, A. Lim, G. Ganteför, B. Kiran, H. Schnöckel, B. Eichhorn, and K. Bowen, J. Chem. Phys. 138, 124303 (2013)]. However, our simulated spectra do not support the assignment of the reported experimental spectrum to AlH2(-).

8.
J Chem Phys ; 135(12): 124312, 2011 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-21974527

RESUMEN

Geometry optimization and harmonic vibrational frequency calculations have been carried out on the X̃(2)A(') state of P(2)H and the X̃(1)A(') state of P(2)H(-) using the restricted-spin coupled-cluster single-double plus perturbative triple excitation [RCCSD(T)] and explicitly correlated unrestricted-spin coupled-cluster single-double plus perturbative triple excitation [UCCSD(T)-F12x] methods. For RCCSD(T) calculations, basis sets of up to the augmented correlation-consistent polarized valence quintuple-zeta (aug-cc-pV5Z) quality were employed, and contributions from extrapolation to the complete basis set limit and from core correlation of the P 2s(2)2p(6) electrons were also included. For UCCSD(T)-F12x calculations, different atomic orbital basis sets of triple-zeta quality with different associated complementary auxiliary basis sets and different geminal Slater exponents were used. When the P 2s(2)2p(6) core electrons were correlated in these F12x calculations, appropriate core-valence basis sets were employed. In addition, potential energy functions (PEFs) of the X̃(2)A(') state of P(2)H and the X̃(1)A(') state of P(2)H(-) were computed at different RCCSD(T) and UCCSD(T)-F12x levels, and were used in variational calculations of anharmonic vibrational wavefunctions, which were then utilized to calculate Franck-Condon factors (FCFs) between these two states, employing a method which includes allowance for anharmonicity and Duschinsky rotation. The photodetachment spectrum of P(2)H(-) was then simulated using the computed FCFs. Simulated spectra obtained using the RCCSD(T)/aug-cc-pV5Z and UCCSD(T)-F12x(x = a or b)/aug-cc-pCVTZ PEFs are compared and found to be essentially identical. Based on the computed FCFs, a more detailed assignment of the observed vibrational structure than previously reported, which includes "hot bands," has been proposed. Comparison between simulated and available experimental spectra has been made, and the currently most reliable sets of equilibrium geometrical parameters for P(2)H and its anion have been derived. The photodetachment spectrum of P(2)D, yet to be recorded, has also been simulated.

9.
Phys Chem Chem Phys ; 13(20): 9540-53, 2011 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-21487636

RESUMEN

RCCSD(T) and UCCSD(T)-F12x calculations were performed on AsX(n) molecules, where X = H, F or Cl, and n = 1, 2 or 3, and related species, in order to evaluate their enthalpies of formation (ΔH(f)(Ø)). The recommended ΔH(f)(Ø) values obtained from the present investigation are AsH, 57.7(2); AsF, -7.9(3); AsCl, 27.2(4); AsH(2), 39.8(4); AsF(2), -96.6(9); AsCl(2), -17.8(10); AsH(3), 17.1(4); AsF(3)-196.0(5) and AsCl(3), -59.1(27) kcal mole(-1). These values are anchored only on one thermodynamic quantity, namely, ΔH(f)(Ø)(As) (= 70.3 kcal mole(-1)). In the calculations, the fully-relativistic small-core effective core potential (ECP10MDF) was used for As. Contributions from outer core correlation of As 3d(10) electrons were computed explicitly in both RCCSD(T) and UCCSD(T)-F12 calculations with additional tight basis functions designed for As 3d(10) electrons. Basis sets of up to augmented correlation-consistent polarized valence quintuple-zeta (aug-cc-pV5Z) quality were used in RCCSD(T) calculations and computed relative electronic energies were extrapolated to the complete basis set (CBS) limit. For the simplified, explicitly correlated UCCSD(T)-F12x calculations, basis sets of up to quadruple-zeta (QZ) quality were employed. Based on the RCCSD(T)/CBS benchmark values, the reliability of available theoretical and experimental values have been assessed.

10.
Phytochem Anal ; 22(6): 503-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21495105

RESUMEN

INTRODUCTION: Isoflavones are main bioactive components of Pueraria lobata (Willd.) Ohwi. Puerarin has been used as the marker compound in herb quality evaluation in the Chinese Pharmacopoiea. However, it is also important to include the other isoflavones present in the herb, such as daidzin, daidzein, genistin and genistein, in the evaluation as they also contribute to the overall bioactivity of the herb. OBJECTIVE: To develop a rapid and reliable method for simultaneous quantitation of isoflavones for P. lobata herb quality evluation. METHODOLOGY: The chromatographic separation was performed on an Agilent rapid resolution liquid chromatographic system through gradient elution. The developed method for the quantification of puerarin, daidzin, daidzein, genistin and genistein was fully validated. When it was applied to analyse the extracts of P. lobata, baseline separation was obtained within 10 min. RESULTS: The amounts of puerarin, daidzin, daidzein and genistin varied greatly among the samples although their chromatographic fingerprints were similar to each other. The 19 samples studied were classified into three clusters (I-III) by principal component analysis based on the amounts of puerarin, daidzin, daidzein and genistin. CONCLUSION: The classification result can be related to herbal origins, but the classification outcome from the chromatographic fingerprinting similarity approach did not provide any geographical origin information. This shows that bioactive constituents can reflect the intrinsic quality of P. lobata more accurately.


Asunto(s)
Isoflavonas/química , Análisis de Componente Principal , Pueraria/química , Cromatografía Liquida/instrumentación , Cromatografía Liquida/métodos , Cromatografía Liquida/normas , Geografía , Límite de Detección , Extractos Vegetales/química , Extractos Vegetales/clasificación , Control de Calidad
11.
J Comput Chem ; 32(8): 1648-60, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21328405

RESUMEN

The currently most reliable theoretical estimates of the adiabatic ionization energies (AIE(0)) from the X̃(2)B(1) state of AsCl(2) to the X̃(1)A(1) and ã(3)B(1) states of AsCl 2+, and the electron affinity (EA(0)) of AsCl(2) , including ΔZPE corrections, are calculated as 8.687(11), 11.320(23), and 1.845(12) eV, respectively (estimated uncertainties based on basis-set effects at the RCCSD(T) level). State-of-the-art ab initio calculations, which include RCCSD(T), CASSCF/MRCI, and explicitly correlated RHF/UCCSD(T)-F12x (x = a or b) calculations with basis sets of up to quintuple-zeta quality, have been carried out on the X̃(2)B(1) state of AsCl(2) , the X̃(1)A(1) , ã(3)B(1) , and Ã(1)B(1) states of AsCl 2+, and the X̃(1)A(1) state of AsCl 2-. Relativistic, core correlation and complete basis-set (CBS) effects have been considered. In addition, computed UCCSD(T)-F12a potential energy functions of relevant electronic states of AsCl(2) , AsCl (2)(+), and AsCl( 2)(-) were used to calculate Franck-Condon factors, which were then used to simulate the valence photoelectron spectrum of AsCl(2) and the photodetachment spectrum of AsCl (2)(-), both yet to be recorded. Lastly, we have also computed the AIE and EA values for NCl(2) , PCl(2) , and AsCl(2) at the G4 level and for SbCl(2) at the RCCSD(T)/CBS level. The trends in the AIE and EA values of the group V pnictogen dichlorides, PnCl(2) , where Pn = N, P, As, and Sb, were examined. The AIE and EA of PCl(2) were found to be smaller than those of AsCl(2) , contrary to the order expected from the IE values of P and As.

12.
J Chem Phys ; 132(23): 234309, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20572707

RESUMEN

Restricted-spin coupled-cluster single-double plus perturbative triple excitation {RCCSD(T)} calculations were carried out on the X (2)B(1) and A (2)A(1) states of AsH(2) employing the fully relativistic small-core effective core potential (ECP10MDF) for As and basis sets of up to the augmented correlation-consistent polarized valence quintuple-zeta (aug-cc-pV5Z) quality. Minimum-energy geometrical parameters and relative electronic energies were evaluated, including contributions from extrapolation to the complete basis set limit and from outer core correlation of the As 3d(10) electrons employing additional tight 4d3f2g2h functions designed for As. In addition, simplified, explicitly correlated CCSD(T)-F12 calculations were also performed employing different atomic orbital basis sets of up to aug-cc-pVQZ quality, and associated complementary auxiliary and density-fitting basis sets. The best theoretical estimate of the relative electronic energy of the A (2)A(1) state of AsH(2) relative to the X (2)B(1) state including zero-point energy correction (T(0)) is 19,954(32) cm(-1), which agrees very well with available experimental T(0) values of 19,909.4531(18) and 19,909.4910(17) cm(-1) obtained from recent laser induced fluorescence and cavity ringdown absorption spectroscopic studies. In addition, potential energy functions (PEFs) of the X (2)B(1) and A (2)A(1) states of AsH(2) were computed at different RCCSD(T) and CCSD(T)-F12 levels. These PEFs were used in variational calculations of anharmonic vibrational wave functions, which were then utilized to calculate Franck-Condon factors (FCFs) between these two states, using a method which includes allowance for anharmonicity and Duschinsky rotation. The A(0,0,0)-X single vibronic level (SVL) emission spectrum of AsH(2) was simulated using these computed FCFs. Comparison between simulated and available experimental vibrationally resolved spectra of the A(0,0,0)-X SVL emission of AsH(2), which consist essentially of the bending (2(n)) series, suggests that there is a significant loss in intensity in the low emission energy region of the experimental spectrum.

13.
Phys Chem Chem Phys ; 12(31): 9075-87, 2010 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-20532314

RESUMEN

RCCSD(T) and/or CASSCF/MRCI calculations were carried out on the X(2)B(1) state of AsF(2), the X(1)A(1), ã(3)B(1) and A(1)B(1) states of AsF(2)(+), and the X(1)A(1) state of AsF(2)(-) employing the fully-relativistic small-core effective core potential (ECP10MDF) for As and basis sets of up to augmented correlation-consistent polarized valence quintuple-zeta (aug-cc-pV5Z) quality. Minimum-energy geometrical parameters and relative electronic energies were evaluated, including contributions from extrapolation to the complete basis set limit and from outer core correlation of the As 3d(10) electrons. In addition, simplified, explicitly correlated RHF/UCCSD(T)-F12x calculations were also performed employing different atomic orbital basis sets, and associated complementary auxiliary and density-fitting basis sets. The best theoretical estimates of the adiabatic ionization energies (AIE(0)) of AsF(2)(X(2)B(1)) to the X(1)A(1) and ã(3)B(1) states of AsF(2)(+), including corrections for zero-point vibrational energy (DeltaZPE), are 9.099(8) and 13.290(22) eV respectively. The best estimated electron affinity (EA(0)) of AsF(2) is 1.182(16) eV, also including Delta(ZPE). These are currently the most reliable AIE(0) and EA(0) values for AsF(2). Potential energy functions (PEFs) of the X(2)B(1) state of AsF(2), the X(1)A(1) and ã(3)B(1) states of AsF(2)(+) and X(1)A(1) state of AsF(2)(-) were computed at RCCSD(T)/aug-cc-pV5Z, RCCSD(T)/aug-cc-pCV5Z and RHF/UCCSD(T)-F12a/aug-cc-pCVTZ levels. These PEFs were employed in variational calculations of anharmonic vibrational wavefunctions, which were then utilised to calculate Franck-Condon factors (FCFs), using a method which includes allowance for anharmonicity and Duschinsky rotation. The computed FCFs were used to simulate the first two bands in the photoelectron spectrum of AsF(2) and the first band in the photodetachment spectrum of AsF(2)(-), both yet to be recorded. The simulated spectra obtained using different sets of PEFs were found to be almost identical, suggesting that the simplified explicitly correlated UCCSD(T)-F12x method with a relatively small basis set can be a reliable alternative to the conventional RCCSD(T) correlation methods with a relatively large basis set, but at a significantly lower cost.

14.
J Comput Chem ; 31(3): 476-91, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19499544

RESUMEN

CCSD(T) and/or CASSCF/MRCI calculations have been carried out on the X(1)A' and A(1)A'' states of HGeCl. The fully relativistic effective core potential, ECP10MDF, and associated standard valence basis sets of up to the aug-cc-pV5Z quality were employed for Ge. Contributions from core correlation and extrapolation to the complete basis set limit were included in determining the computed equilibrium geometrical parameters and relative electronic energy of these two states of HGeCl. Based on the currently, most systematic CCSD(T) calculations performed in this study, the best theoretical geometrical parameters of the X(1)A' state are r(e)(HGe) = 1.580 +/- 0.001 A, theta(e) = 93.88 +/- 0.01 degrees and r(e)(GeCl) = 2.170 +/- 0.001 A. In addition, Franck-Condon factors including allowance for anharmonicity and Duschinsky rotation between these two states of HGeCl and DGeCl were calculated employing CCSD(T) and CASSCF/MRCI potential energy functions, and were used to simulate A(1)A'' --> X(1)A' SVL emission spectra of HGeCl and DGeCl. The iterative Franck-Condon analysis (IFCA) procedure was carried out to determine the equilibrium geometrical parameters of the A(1)A'' state of HGeCl by matching the simulated, and available experimental SVL emission spectra of HGeCl and DGeCl of Tackett et al., J Chem Phys 2006, 124, 124320, using the available, estimated experimental equilibrium (r(e)(z)) structure for the X(1)A' state, while varying the equilibrium geometrical parameters of the A(1)A'' state systematically. Employing the derived IFCA geometry of r(e)(HGe) = 1.590 A, r(e)(GeCl) = 2.155 A and theta(e)(HGeCl) = 112.7 degrees for the A(1)A'' state of HGeCl in the spectral simulation, the simulated absorption and SVL emission spectra of HGeCl and DGeCl agree very well with the available experimental LIF and SVL emission spectra, respectively.


Asunto(s)
Algoritmos , Cloruros/química , Germanio/química , Teoría Cuántica , Vibración , Simulación por Computador , Electrones , Espectrofotometría , Termodinámica
15.
Anal Chem ; 81(17): 7217-25, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19634860

RESUMEN

Using whole chromatographic profiles and measurements of total bioactivity as input, a quantitative pattern-activity relationship (QPAR) approach is proposed as a general method for providing two pieces of crucial information about complex bioactive mixtures available: (i) a model for predicting total bioactivity from the chromatographic fingerprint and (ii) the features in the chromatographic profile responsible for the bioactivity. While the first piece of information is already available through existing approaches, the second one results from our ability to remove dominant features in the chromatographic fingerprints which mask the components specifically related to pharmacological activity. Our targeted approach makes information about bioactivity available at the molecular level and provides possibilities for assessment of herbal medicine (HM) possible beyond just authentication and total bioactivity. As an example, the antioxidant property of the HM Radix Puerariae lobatae is measured through its reducing power toward a ferric ion complex. A partial least-squares (PLS) model is created to predict the antioxidant activity from the chromatographic fingerprint. Using the antioxidant activity as a target, the most discriminatory projection in the multivariate space spanned by the chromatographic profiles is revealed. From this target-projected component, the chromatographic regions most strongly connected to antioxidant activity are identified using the so-called selectivity ratio (SR) plot. The results are validated by prediction of samples not included in the modeling step.


Asunto(s)
Antioxidantes/análisis , Antioxidantes/farmacología , Cromatografía/métodos , Medicamentos Herbarios Chinos/análisis , Medicina de Hierbas/métodos , Pueraria/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Flavonoides/análisis , Análisis de los Mínimos Cuadrados , Reproducibilidad de los Resultados
16.
Acta Biomater ; 5(8): 2913-9, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19463980

RESUMEN

Puerarin nanoparticles were firstly prepared in the process of solution-enhanced dispersion by supercritical CO(2) (SEDS) and then successfully microencapsulated by poly(l-lactide) (PLLA) in a modified SEDS process. By adding an organic non-solvent, an initial puerarin solution with a higher degree of saturation and lower concentration was obtained and applied in the SEDS process. The resulting puerarin nanoparticles were then suspended in PLLA solution and microencapsulated by PLLA in a modified SEDS process, where an 'injector' was employed in the particle suspension delivery system. The puerarin nanoparticles exhibited a good spherical shape, a smooth surface and a narrow particle size distribution with a mean particle size of 188 nm. After microencapsulation the puerarin-PLLA microparticles had a mean size of 675 nm, a drug load of 23.6% and an encapsulation efficiency of 39.4%; after a burst release at the first stage, the drug was released in a sustained process. Compared with the parallel study of a co-precipitation process, this microencapsulation process is a much more promising technique to prepare a drug-polymer carrier for a drug delivery system, especially for protein drugs.


Asunto(s)
Materiales Biocompatibles/química , Cromatografía con Fluido Supercrítico/métodos , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Isoflavonas/química , Nanopartículas/química , Nanopartículas/ultraestructura , Poliésteres/química , Absorción , Cápsulas , Cristalización/métodos , Difusión , Isoflavonas/administración & dosificación , Ensayo de Materiales , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Vasodilatadores/administración & dosificación , Vasodilatadores/química
17.
J Sep Sci ; 32(4): 660-70, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19212980

RESUMEN

Systematic comparative research was conducted on essential oils from eight traditional Chinese medicines (TCM) of pungent flavor and cool nature because the essential oils are the main active ingredients of herbs of this kind. The work was based on their component analysis by gas chromatography-mass spectrometry (GC-MS), on their retention indices, as well as on chemometric resolution methods. A total of 144 compounds were tentatively identified, accounting for 69.0% to 91.8% of the total essential oils. It is worth noting that there are 67 compounds in at least three of these eight essential oils. Moreover, many biologically active compounds, such as hexanal, alpha-pinene, camphene, beta-pinene, p-cymene, limonene, eucalyptol, (Z)-ocimene, gamma-terpinene, camphor, p-menthone, 4-terpineol, alpha-terpineol, carvone, eugenol, caryophyllene, beta-farnesene, alpha-curcumene, beta-selinene, delta-cadinene, caryophyllene oxide, cedrol, n-hexadecanoic acid, benzaldehyde, benzeneacetaldehyde, phthalic acid diisobutyl ester, linoleic acid, tetradecanoic acid, (Z,Z,Z)-9,12,15-octadecatrienoic acid, eucalyptol, pentadecanoic acid, hexadecanoic acid methyl ester, linoleic acid methyl ester, exist in at least four of the eight essential oils. These results might help us to understand why the eight herbs are all of pungent flavor and cool nature according to the theory of TCM, and may provide a useful chemical basis for future research on herbs of this kind.


Asunto(s)
Productos Biológicos/análisis , Productos Biológicos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Aceites Volátiles/análisis , Aceites Volátiles/química , Medicina de Hierbas
18.
J Chromatogr A ; 1216(11): 2130-5, 2009 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-19185872

RESUMEN

A new, rapid analytical method using near-infrared spectroscopy (NIRS) was developed to differentiate two species of Radix puerariae (GG), Pueraria lobata (YG) and Pueraria thomsonii (FG), and to determine the contents of puerarin, daidzin and total isoflavonoid in the samples. Five isoflavonoids, puerarin, daidzin, daidzein, genistin and genistein were analyzed simultaneously by high-performance liquid chromatography-diode array detection (HPLC-DAD). The total isoflavonoid content was exploited as critical parameter for successful discrimination of the two species. Scattering effect and baseline shift in the NIR spectra were corrected and the spectral features were enhanced by several pre-processing methods. By using linear discriminant analysis (LDA) and soft independent modeling class analogy (SIMCA), samples were separated successfully into two different clusters corresponding to the two GG species. Furthermore, sensitivity and specificity of the classification models were determined to evaluate the performance. Finally, partial least squares (PLS) regression was used to build the correlation models. The results showed that the correlation coefficients of the prediction models are R=0.970 for the puerarin, R=0.939 for daidzin and R=0.969 for total isoflavonoid. The outcome showed that NIRS can serve as routine screening in the quality control of Chinese herbal medicine (CHM).


Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/normas , Isoflavonas/análisis , Pueraria/química , Espectroscopía Infrarroja Corta/métodos , Algoritmos , Cromatografía Líquida de Alta Presión , Análisis por Conglomerados , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Modelos Químicos , Control de Calidad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
J Comput Chem ; 30(3): 337-45, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18629874

RESUMEN

Restricted-spin coupled-cluster single-double plus perturbative triple excitation {RCCSD(T)} potential energy functions (PEFs) of the X(2)B2 state of ScO2 and the 1A1 state of ScO2(-) were computed, employing the augmented correlation-consistent polarized-weighted core-valence quadruple-zeta (aug-cc-pwCVQZ) basis set for Sc and augmented correlation-consistent polarized valence quadruple-zeta (aug-cc-pVQZ) basis set for O, and with the outer core Sc 3s(2)3p(6) electrons being explicitly correlated. Franck-Condon factors, which include allowance for Duschinsky rotation and anharmonicity, were calculated using the computed RCCSD(T) PEFs, and were used to simulate the first photodetachment band of ScO2(-). The simulated spectrum matches well with the corresponding experimental 355 nm photodetachment spectrum of Wu and Wang, J Phys Chem A 1998, 102, 9129, confirming the assignment of the photodetachment spectrum and the reliability of the RCCSD(T) PEFs used. Further calculations on low-lying electronic states of ScO2 gave adiabatic relative electronic energies (T(e)'s) of, and vertical excitation energies (T(v)'s) to, the 2A1, 2B1, and 2A2 states of ScO2 (from the X(2)B2 state of ScO2), as well as electron affinities (EAs) and vertical detachment energies (VDEs) to these neutral states from the 1A1 state of ScO2(-).


Asunto(s)
Simulación por Computador , Modelos Químicos , Óxidos/química , Teoría Cuántica , Escandio/química , Fotoquímica
20.
J Chem Theory Comput ; 5(3): 565-79, 2009 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26610223

RESUMEN

RCCSD(T) and/or CASSCF/MRCI calculations have been carried out on the X̃(1)A' and Ã(1)A'' states of HSiCl employing basis sets of up to the aug-cc-pV5Z quality. Contributions from core correlation and extrapolation to the complete basis set limit were included in determining the computed equilibrium geometrical parameters and relative electronic energy of these two states of HSiCl. Franck-Condon factors which include allowance for anharmonicity and Duschinsky rotation between these two states of HSiCl and DSiCl were calculated employing RCCSD(T) and CASSCF/MRCI potential energy functions, and were used to simulate the Ã(1)A'' ← X̃(1)A' absorption and Ã(1)A'' → X̃(1)A' single vibronic level (SVL) emission spectra of HSiCl and DSiCl. Simulated absorption and experimental LIF spectra, and simulated and observed Ã(1)A''(0,0,0) → X̃(1)A' SVL emission spectra, of HSiCl and DSiCl are in very good agreement. However, agreement between simulated and observed Ã(1)A''(0,1,0) → X̃(1)A' and Ã(1)A''(0,2,1) → X̃(1)A' SVL emission spectra of DSiCl is not as good. Preliminary calculations on low-lying excited states of HSiCl suggest that vibronic interaction between low-lying vibrational levels of the Ã(1)A'' state and highly excited vibrational levels of the ã(3)A'' is possible. Such vibronic interaction may change the character of the low-lying vibrational levels of the Ã(1)A'' state, which would lead to perturbation in the SVL emission spectra from these vibrational levels.

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