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1.
Zhongguo Zhong Yao Za Zhi ; 48(13): 3535-3545, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37474987

RESUMO

This study aims to evaluate the quality consistency of Saposhnikoviae Radix based on carbohydrates, and explore the potential of carbohydrates as the internal quality control indicators of Saposhnikoviae Radix. The total polysaccharides were quantified by UV-Vis spectrophotometry and the molecular weight range of the polysaccharides was determined by high performance gel-permeation chromatography-evaporative light scattering detection(HPGPC-ELSD). The monosaccharides in polysaccharides and the free monosaccharides were quantified by high performance liquid chromatography-UV detection(HPLC-UV), and the oligosaccharides and fructose were quantified by high performance liquid chromatography-evaporative light scattering detection(HPLC-ELSD). The carbohydrate-based quality of Saposhnikoviae Radix was compared among 45 batches of commercial samples and 13 batches of self-collected samples. The results showed that the molecular weight distribution, monosaccharide composition, oligosaccharide, and free monosaccharide composition were similar in the 58 batches of samples. The average content of total polysaccharides, oligosaccharides, and total free monosaccharides in commercial samples were 39.66, 148.79, and 68.62 mg·g~(-1), respectively. The content showed significant differences among batches, with the highest differences of 3.51, 1.75, and 2.58 times, respectively. The RSD of the relative ratios of monosaccharides in the polysaccharides in commercial samples reached 28%-45%. The average content of total polysaccharides, oligosaccharides, and total free monosaccharides in self-collected samples were 68.07, 145.76, and 42.04 mg·g~(-1), respectively, with the inter-region differences of 2.88, 1.88, and 1.07 times, respectively. The RSD of the relative ratios of monosaccharides in polysaccharides in self-collected samples ranged from 8.2% to 59%. The total polysaccharides and total free monosaccharides in self-collected samples were 1.72 times higher and 1.63 times lower, respectively, than those in commercial samples. The content of oligosaccharides was similar between self-collected samples and commercial samples. To sum up, carbohydrates are one of the material bases for the internal quality consistency of Saposhnikoviae Radix. The qualitative characteristics of polysaccharides and the quantitative characteristics of polysaccharides and oligosaccharides are related to the origin of medicinal materials. Moreover, the quantitative characteristics of polysaccharides and free monosaccharides may be related to the storage conditions. Carbohydrates are potential indicators for the quality control of Saposhnikoviae Radix and deserve attention.


Assuntos
Carboidratos , Monossacarídeos , Polissacarídeos , Cromatografia Líquida de Alta Pressão/métodos , Oligossacarídeos
2.
J Ethnopharmacol ; 298: 115601, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35963422

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Chang-Kang-Fang (CKF) is a traditional Chinese herbal formula used for treatment of irritable bowel syndrome (IBS) in China. Decoction is the administration form of CKF in clinical practice. Previously, CKF has been confirmed with activities of releasing pain and reversing disorders of intestinal propulsion. And alkaloids, monoglycosides, chromones were found as the main bioactive components potentially contributing to the efficacy of CKF. Polysaccharide was also a major constituent in CKF. But if and how polysaccharides influence the systemic exposure of bioactive components in CKF is unknown. AIM OF THE STUDY: In this study, we aimed to demonstrate the contribution of the co-existed polysaccharides on the systemic exposure of the major bioactive components from CKF in normal and IBS model rats. MATERIALS AND METHODS: An UPLC-TQ-MS with multiple reaction monitoring (MRM) scan method was developed and validated for quantifying six major small molecular bioactive ingredients of CKF in the plasma samples, including magnoflorine (MAG), berberine (BBR), albiflorin (ALB), paeoniflorin (PAE), 5-O-methylvisamminol (5-OM) and prim-O-glucosylcimifugin (POG). The rats received CKF decoction (CKF) and CKF small molecule portion (knockout of polysaccharides, CKFSM), respectively. IBS model rats were induced by daily bondage and gavage of Sennae Folium decoction (derived from the leaf of Cassia angustifolia Vahl). The effects of the co-existing polysaccharides on the pharmacokinetic parameters of six small molecular bioactive components in normal and IBS model rats were systematically evaluated. The potential gut microbiota involved mechanisms of the effects was validated by broad-spectrum antibiotic (ABX) treatment. RESULTS: The selectivity, precision, accuracy, recovery and matrix effect of the established quantification method were all within acceptable limits of biological sample. In normal rats, the co-existing polysaccharides significantly reduced the AUC(0-t) of MAG and PAE compared with CKFSM group. The Cmax and AUC(0-t) of other four compound were not influenced by co-existing polysaccharides. However, in IBS model rats, compared with CKFSM group, the Cmax and AUC(0-t) of the six ingredients significantly increased in CKF group. For CKF + ABX group, the Cmax of six ingredients decreased significantly when compared with CKF group, and the AUC(0-t) of MAG, BBR, ALB, PAE also reduced with significant differences. CONCLUSIONS: A reliable and sensitive UPLC-TQ-MS method was successfully developed and validated for evaluating influence of co-existing polysaccharides on pharmacokinetic behavior of six major small molecules components in CKF. The co-existing polysaccharides enhanced the systemic exposure of six bioactive small molecules in CKF under IBS pathological state potentially via gut microbiota involvement.


Assuntos
Medicamentos de Ervas Chinesas , Síndrome do Intestino Irritável , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/patologia , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Prescrições , Ratos , Ratos Sprague-Dawley
3.
IEEE Trans Cybern ; 52(11): 12302-12314, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33961575

RESUMO

This work proposes a nonparametric prior induced deep sum-logarithmic-multinomial mixture (DSLMM) model to detect pilots' cognitive states through the developed brain power map. DSLMM uses multinormal distribution to infer the latent variable of each neuron in the first layer of the network. These latent variables obeyed a sum-logarithmic distribution that is backpropagated to its observation vector and the number of neurons in the next layer. Multinormal distribution is used to segment the extended observation vector to form a matrix associated with the width of the next layer. This work also proposes an adaptive topic-layer stochastic gradient Riemann (ATL-SGR) Markov chain Monte Carlo (MCMC) inference method to learn its global parameters without heuristic assumptions. The experimental results indicate that DSLMM can extract more probability distribution contained in the brain power map layer by layer, and achieve higher pilot cognition detection accuracy.


Assuntos
Pilotos , Encéfalo , Cognição , Humanos , Aprendizagem , Cadeias de Markov , Pilotos/psicologia
4.
J Pharm Biomed Anal ; 203: 114186, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34118572

RESUMO

Chang-Kang-Fang formula (CKF), a multi-herbs traditional Chinese medicine (TCM) prescription for treating irritable bowel syndrome (IBS), has been clinically applied in the traditional form of mixed-herb decoction (MHD), or in the modern form of combined single-herb decoction (cSHD, so called dispensing granule decoction) in the near decades, but the chemical consistency between the MHD and cSHD is still unknown. Herein, a new strategy by integrating multiple-chromatographic approaches to characterize both polysaccharides and small molecules was developed to compare the chemical consistency between MHD and cSHD. Sixteen small molecules were simultaneously qualified and quantified by UPLC-QTOF-MS/MS, the molecular weight distribution of polysaccharides was characterized by HPGPC-ELSD, while the monosaccharide composition and total saccharides content were determined by HPLC-PDA and UV-VIS, respectively. It was found that the molecular weight range and monosaccharide composition of polysaccharides, as well as the composition of small molecules, were identical between MHD and cSHD. However, the contents of berberine, epiberberine, coptisine, palmatine, albiflorin and paeoniflorin in MHD were significantly lower than those in cSHD, whereas the content of polysaccharides in MHD was higher than that in cSHD, indicating that there is a significant difference in the quality between MHD and cSHD, in particular for the relative contents of major small molecules and polysaccharides. Whether or not these quality variations affect the efficacy and safety of CKF deserves further investigation.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa
5.
IEEE Trans Cybern ; 51(1): 332-345, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30640640

RESUMO

How to track the attention of the pilot is a huge challenge. We are able to capture the pupil status of the pilot and analyze their anomalies and judge the attention of the pilot. This paper proposes a new approach to solve this problem through the integration of spherical Haar wavelet transform and deep learning methods. First, considering the application limitations of Haar wavelet and other wavelets in spherical signal decomposition and reconstruction, a feature learning method based on the spherical Haar wavelet is proposed. In order to obtain the salient features of the spherical signal, a rotating spherical Haar wavelet is also proposed, which has a consistent scale in the same direction between the reconstructed image and the original image. Second, in order to find a better characteristic representation of the spherical signal, a higher contractive autoencoder (HCAE) is designed for the potential representation of the spherical Haar wavelet coefficients, which has two penalty items, respectively, from Jacobian and two order items from Taylor expansion of the point x for the contract learning of sample space. Third, in order to improve the classification performance, this paper proposes a fuzzy Gaussian support vector machine (FGSVM) as the top classification tool of the deep learning model, which can punish some Gaussian noise from the output of the deep HCAE network (DHCAEN). Finally, a DHCAEN-FGSVM classifier is proposed to identify the location of the pupil center. The experimental results of the public data set and actual data show that our model is an effective method for spherical signal detection.

6.
J Pharm Biomed Anal ; 192: 113665, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33120311

RESUMO

Cicadae Periostracum (CP), the cast-off shell of Cryptotympana atrata, is specified in Chinese Pharmacopoeia for relieving fever and eliminating ulcer. N-acetyldopamine oligomers are the major characteristic bioactive components with antioxidant and anti-inflammatory activities that may be responsible for the efficacy of CP. However, the exposed components and metabolites of N-acetyldopamine oligomers of CP (NOCP) in vivo are still unknown. In present study, the metabolic profile of total NOCP and N-acetyldopamine dimer B in rats were systematically investigated by ultra-high liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). In biosamples of NOCP group, 34 prototypes and 15 metabolites were identified or tentatively characterized, including 5 metabolites in plasma, 3 prototype and 9 metabolites in urine, 2 metabolites in bile, 34 prototypes and 8 metabolites in feces, respectively. In dimer B group, the prototype and 8 metabolites were identified, including 2 metabolites in plasma, 4 metabolites in urine, 1 metabolite in bile and 5 metabolites in feces, respectively. Oxidation, and hydrogenation were supposed to be the major phase I reactions, while methylation, sulfation, and glucuronidation were the main phase II reactions of NOCP and dimer B. M10 and M13 might undergo enterohepatic circulation in rats. It is concluded that NOCP and dimer B were mainly absorbed in the form of metabolites, and metabolites are probably the major bioactive forms of NOCP and dimer B. The outcomes of this study provided helpful information for extensively elucidating biological and pharmacological mechanisms of NOCP.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Dopamina/análogos & derivados , Ratos , Ratos Sprague-Dawley
7.
J Pharm Biomed Anal ; 179: 112974, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31767224

RESUMO

Cicadae Periostracum, which is derived from the slough of Cicadidae insects, is a commonly used crude drug in traditional Chinese medicine (TCM). As specified in Chinese Pharmacopoeia, Cryptotympana atrata (CA) is the only official species of this crude drug. However, the slough of other three species, i.e., Auritibicen flammatus (AF), Cryptotympana mandrina (CM) and Platypleura kaempferi (PK), have been also used as the origins of Cicadae Periostracum in Chinese herbal market, although whether the quality of these four origins is consistent or not is still unknown. In present study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was employed to qualitatively and quantitatively compare the chemical profiles of the four origins. Totally, 34 N-acetyldopamine polymers were identified from the four origins, including 4 N-acetyldopamine dimers, 11 N-acetyldopamine trimers, 10 N-acetyldopamine tetramers, and 9 N-acetyldopamine pentamers. AF, CM and PK had similar chemical profiles with that of CA. The contents and compositional ratio of the four types of polymers in CA, AF and CM were consistent with each other, but significantly lower or different in PK. All these results suggested that AF and CM might be considered as the potential resources of Cicadae Periostracum concerning their consistent holistic quality, whereas whether PK could be used as potential origin of Cicadae Periostracum or not need further evaluation for their different compositional ratios and contents of the four types of N-acetyldopamine polymers. This is the first study on chemical profiling and comparison of N-acetyldopamine polymers in four origins of Cicadae Periostracum, which is beneficial for potential resources utilization and quality standard improvement of Cicadae Periostracum.


Assuntos
Dopamina/análogos & derivados , Medicamentos de Ervas Chinesas/química , Hemípteros/química , Animais , Cromatografia Líquida de Alta Pressão , Dopamina/análise , Polímeros/análise , Espectrometria de Massas em Tandem
8.
Opt Express ; 20(4): 4454-69, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22418205

RESUMO

Accurate conversion of wideband multi-GHz analog signals into the digital domain has long been a target of analog-to-digital converter (ADC) developers, driven by applications in radar systems, software radio, medical imaging, and communication systems. Aperture jitter has been a major bottleneck on the way towards higher speeds and better accuracy. Photonic ADCs, which perform sampling using ultra-stable optical pulse trains generated by mode-locked lasers, have been investigated for many years as a promising approach to overcome the jitter problem and bring ADC performance to new levels. This work demonstrates that the photonic approach can deliver on its promise by digitizing a 41 GHz signal with 7.0 effective bits using a photonic ADC built from discrete components. This accuracy corresponds to a timing jitter of 15 fs - a 4-5 times improvement over the performance of the best electronic ADCs which exist today. On the way towards an integrated photonic ADC, a silicon photonic chip with core photonic components was fabricated and used to digitize a 10 GHz signal with 3.5 effective bits. In these experiments, two wavelength channels were implemented, providing the overall sampling rate of 2.1 GSa/s. To show that photonic ADCs with larger channel counts are possible, a dual 20-channel silicon filter bank has been demonstrated.

9.
Zhong Yao Cai ; 34(6): 893-5, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22017004

RESUMO

OBJECTIVE: To study the chemical constituents of roots of Rumex patientia. METHODS: The compounds were separated and purified by silica column chromatopraphy, Sephadex LH-20 and identified by several spectroscopic methods. RESULTS: Seven constituents were identified as nepodin (1), nepodin-8-O-beta-D-glucopyranoside (2), chrysophanol-8-O-beta-D-glucopyranoside (3), emodin-6-O-beta-D-glucopyranoside (4), emodin-8-O-beta-D-glucopyranoside (5), 1, 3, 5-trihydroxy-7-methylanthraquinone (6), physcion-8-O-beta-D-glucopyranoside (7), respectively. CONCLUSION: Compound 1 is isolated from this plant for the first time and compound 6 is isolated from Rumex L. for the first time.


Assuntos
Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Rumex/química , Antraquinonas/química , Antraquinonas/isolamento & purificação , Glucosídeos/química , Glucosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Solventes/química
10.
Opt Express ; 16(8): 5218-26, 2008 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-18542624

RESUMO

We present a systematic study of Mach-Zehnder silicon optical modulators based on carrier-injection. Detailed comparisons between modeling and measurement results are made with good agreement obtained for both DC and AC characteristics. A figure of merit, static VpiL, as low as 0.24Vmm is achieved. The effect of carrier lifetime variation with doping concentration is explored and found to be important for the modulator characteristics.


Assuntos
Desenho Assistido por Computador , Modelos Teóricos , Óptica e Fotônica/instrumentação , Silício/química , Telecomunicações/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento
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