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1.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1196-1205, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38621966

RESUMO

Processing of Chinese medicinal materials is an important part in the Chinese medicine heritage, and the temperature control in the processing has a direct impact on the quality and efficacy of traditional Chinese medicines. However, the processing of Chinese medicinal materials has the problems of subjective temperature judgement, determination of the end point based on experience, unclear processing mechanism, unstable quality of products, and inconsistent processing standards. The temperature control in the processing is reflected in the appearance and internal quality of Chinese medicinal materials. The theory of quality evaluation through morphological identification is developed based on the comprehensive evaluation of the shape, color, taste, and components, which is associated with the temperature control in the processing. To solve the problems above, this paper puts forward the following solutions. The first is literature mining. By review of the ancient medical works and pharmaceutical experience, the temperature control in processing and the evolution of processing methods can be revealed. Second, according to the ancient method, the processing principle can be explored, on the basis of which the processing technology can be innovated. Third, the standard operating procedure(SOP) should be established to quantify the fire temperature, providing a theoretical basis for the formulation of Chinese medicinal material processing standards. Moreover, it provides a basis for improving the quality of processed products and increasing the safety and effectiveness of traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas , Humanos , Temperatura , Medicina Tradicional Chinesa , Padrões de Referência , Tecnologia
2.
Phys Rev Lett ; 131(1): 016201, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478456

RESUMO

In twisted h-BN/graphene heterostructures, the complex electronic properties of the fast-traveling electron gas in graphene are usually considered to be fully revealed. However, the randomly twisted heterostructures may also have unexpected transition behaviors, which may influence the device performance. Here, we study the twist-angle-dependent coupling effects of h-BN/graphene heterostructures using monochromatic electron energy loss spectroscopy. We find that the moiré potentials alter the band structure of graphene, resulting in a redshift of the intralayer transition at the M point, which becomes more pronounced up to 0.22 eV with increasing twist angle. Furthermore, the twisting of the Brillouin zone of h-BN relative to the graphene M point leads to tunable vertical transition energies in the range of 5.1-5.6 eV. Our findings indicate that twist-coupling effects of van der Waals heterostructures should be carefully considered in device fabrications, and the continuously tunable interband transitions through the twist angle can serve as a new degree of freedom to design optoelectrical devices.

3.
Nano Lett ; 22(19): 8018-8024, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-35959969

RESUMO

The structure of amorphous materials has been debated since the 1930s as a binary question: amorphous materials are either Zachariasen continuous random networks (Z-CRNs) or Z-CRNs containing crystallites. It was recently demonstrated, however, that amorphous diamond can be synthesized in either form. Here we address the question of the structure of single-atom-thick amorphous monolayers. We reanalyze the results of prior simulations for amorphous graphene and report kinetic Monte Carlo simulations based on alternative algorithms. We find that crystallite-containing Z-CRN is the favored structure of elemental amorphous graphene, as recently fabricated, whereas the most likely structure of binary monolayer amorphous BN is altogether different than either of the two long-debated options: it is a compositionally disordered "pseudo-CRN" comprising a mix of B-N and noncanonical B-B and N-N bonds and containing "pseudocrystallites", namely, honeycomb regions made of noncanonical hexagons. Implications for other nonelemental 2D and bulk amorphous materials are discussed.

4.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1194-1202, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005803

RESUMO

Ionic liquids(ILs) are salts composed entirely of anions and cations in a liquid state at or near room temperature, which have a variety of good physicochemical properties such as low volatility and high stability. This paper mainly reviewed the research overview of ILs in the application of traditional Chinese medicine(TCM) volatile oil preparation technology. Firstly, it briefly introduced the application of TCM volatile oil preparation technology and composition classification and physicochemical properties of ILs, and then summarized the application of ILs in the extraction, separation, analysis, and preparation of TCM volatile oil. Finally, the problems and challenges of ILs in the application of TCM volatile oil were explained, and the application of ILs in TCM volatile oil in the future was prospected.


Assuntos
Produtos Biológicos , Líquidos Iônicos , Óleos Voláteis , Cátions , Líquidos Iônicos/química , Medicina Tradicional Chinesa , Óleos Voláteis/análise , Tecnologia
5.
Zhongguo Zhong Yao Za Zhi ; 48(7): 1800-1807, 2023 Apr.
Artigo em Zh | MEDLINE | ID: mdl-37282954

RESUMO

In recent years, the use of active substances as excipients or as substitutes for other excipients in the design of modern drug delivery systems has received widespread attention, which has promoted the development of the theory of unification of medicines and excipients in the design of traditional Chinese medicine(TCM) preparations. Adopting the theory of unification of medicines and excipients to design drug delivery systems can reduce the use of excipients and thus the cost of preparations, reduce drug toxicity, increase drug solubility and biocompatibility, enhance synergistic effect, and realize targeted delivery and simultaneous delivery of multiple components. However, the research on the application of this theory in the modern drug delivery system of TCM preparations is still insufficient, with few relevant articles. In addition, the TCM active substances that can be used as the excipients remain to be catalogued. In this paper, we review the types and applications of the drug delivery systems with TCM active substances as excipients and describe their common construction methods and mechanisms, aiming to provide references for the in-depth research on the modern drug delivery systems for TCM preparations.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Excipientes , Nanomedicina , Preparações Farmacêuticas
6.
Zhongguo Zhong Yao Za Zhi ; 47(3): 603-610, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35178942

RESUMO

Essential oils from Chinese medicine are popular in the fields such as medicine, food, and cosmetics because of their unique biological characteristics. However, since essential oils are lipophilic compounds with high volatility, poor stability, and strong irritation, various preparation technologies need to be employed to improve stability, reduce irritation, and increase bioavailability. At present, a variety of preparation technologies have been applied to the encapsulation of essential oils. Various encapsulation strategies are formed because of different delivery systems featured with multiple principles and characteristics and are widely used to improve the stability of essential oils. Essential oils of Chinese medicine are widely used in the medical field, and they are under continuous innovation and development in clinical research, the pharmaceutical industry, medical products, etc. The present study summarized various delivery systems that could improve the stability of essential oils and reviewed the applications of essential oils encapsulated in the delivery systems in the medical field to provide re-ferences for the improvement of stability of essential oils and their safety, efficiency, and wide use in the medical field.


Assuntos
Óleos Voláteis , China
7.
Zhongguo Zhong Yao Za Zhi ; 47(1): 271-278, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-35178934

RESUMO

Due to the characteristics of confusing varieties of Chinese medicinal materials, different sources, complex chemical composition, non-standard preparation process, and non-standard pharmaceutical equipment, the quality of Chinese medicinal preparations is difficult to be controlled and evaluated effectively under the current quality control mode and method of Chinese medicinal preparation. The present study proposed an engineering quality view of Chinese medicine pharmacy and a strategy to control the quality of Chinese medicinal preparations based on the current situation. The "overall, dialectical, and dynamic" multi-factor engineering quality view, covering original medicinal materials, preparation technologies, pharmaceutical equipment, and Chinese medicinal preparations, ensures the traceable process, measurable procedures, and feedback quality. The quality control mode of Chinese medicinal preparation with controllable sources, standardized preparation technologies, green pharmaceutical equipment, and intelligent manufacturing is built up.


Assuntos
Medicamentos de Ervas Chinesas , Farmácia , Comércio , Medicina Tradicional Chinesa , Controle de Qualidade
8.
Yi Chuan ; 35(4): 529-32, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-23659944

RESUMO

In recent years, zebrafish has been found to be strikingly capable of heart regeneration at adult stage, which sheds lights on cardiac regenerative medicine, and has also become an important direction for the study of vertebrate genetic and developmental mechanisms. Dissecting the regeneration process and unraveling the underlying molecular and cellular mechanisms might help recover the regeneration capacity of the mammalian heart and further provide instructions to potential therapies for certain cardiac diseases such as myocardial infarction. Here, we introduced a simple surgical method to construct heart injury and regeneration model in zebrafish through amputation of ~20% ventricle. The main procedure includes anaesthetization of adult zebrafish, exposure of the heart by dissecting the nearby abdominal skin and opening the pericardium, and amputation of certain fraction of the ventricle at the cardiac apex under a stereo microscope. Over 90% success rate and easy handling with high reproducibility enable this method to be the most commonly used one for the study of zebrafish heart regeneration.


Assuntos
Modelos Animais de Doenças , Traumatismos Cardíacos/fisiopatologia , Traumatismos Cardíacos/cirurgia , Coração/fisiopatologia , Regeneração , Peixe-Zebra/cirurgia , Animais , Procedimentos Cirúrgicos Cardíacos , Feminino , Imobilização , Masculino
9.
Adv Mater ; 35(41): e2303455, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37363875

RESUMO

Ammonia (NH3 ) is essential for modern agriculture and industry, and, due to its high hydrogen density and no carbon emission, it is also expected to be the next-generation of "clean" energy carrier. Herein, directly from air and water, a plasma-electrocatalytic reaction system for NH3 production, which combines two steps of plasma-air-to-NOx - and electrochemical NOx - reduction reaction (eNOx RR) with a bifunctional catalyst, is successfully established. Especially, the bifunctional catalyst of CuCo2 O4 /Ni can simultaneously promote plasma-air-to-NOx - and eNOx RR processes. The easy adsorption and activation of O2 by CuCo2 O4 /Ni greatly improve the NOx - production rate at the first step. Further, CuCo2 O4 /Ni can also resolve the overbonding of the key intermediate of * NO, and thus reduce the energy barrier of the second step of eNOx RR. Finally, the "green" NH3 production achieves excellent FENH3 (96.8%) and record-high NH3 yield rate of 145.8 mg h-1  cm-2 with large partial current density (1384.7 mA cm-2 ). Moreover, an enlarged self-made H-type electrolyzer improves the NH3 yield to 3.6 g h-1 , and the obtained NH3 is then rapidly converted to a solid of magnesium ammonium phosphate hexahydrate, which favors the easy storage and transportation of NH3 .

10.
Ying Yong Sheng Tai Xue Bao ; 31(11): 3777-3785, 2020 Nov.
Artigo em Zh | MEDLINE | ID: mdl-33300728

RESUMO

With landsat-series multi-temporal image data, percentage of vegetation cover (PVC) was estimated by pixel dichotomy. The linear regression analysis and center of gravity migration methods were used to explore the characteristics of the spatiotemporal changes of vegetation cover in Shenzhen from 2000 to 2018. The CA-Markov model was combined to predict future land cover in Shenzhen. The results showed that the PVC in Shenzhen demonstrated obvious regional differentiation characteristics from 2000 to 2018. The eastern region occupied larger proportion than the wes-tern part, while the southern region was larger than the north part. This feature exhibited good consistency with regional topographic effect. The spatial migration characteristic of the center of gravity of PVC was from northwest to southeast, and then from southeast to northwest, with a migration rate of 551.2 m·a-1. This process was closely related to urbanization in Shenzhen. The PVC in Shen-zhen tended to be generally improved from 2000-2018, with a improvement rate of 0.005·a-1. The percentage of significantly improved and degraded PVC area was 30.8% and 12.8%, respectively. The CA-Markov method was used to predict the land cover/use pattern of Shenzhen in 2024 under two scenarios, theoretical scenario and natural scenario. There was no significant difference in proportion of the area of the land cover/use patterns obtained by the two kinds of prediction method, with the difference threshold being 0-1.2%. Compared with the data before 2018, the proportion of arbor forests and arable land converted into construction land in Shenzhen would be significantly reduced in 2024, whereas the contradiction between supply and demand would be still tense.


Assuntos
Conservação dos Recursos Naturais , Urbanização , China
11.
Acta Otolaryngol ; 138(2): 175-179, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28990830

RESUMO

OBJECTIVE: To evaluate the clinical value of pulse oximetry watch (POW) for diagnosing pediatric Obstructive sleep apnea/hypopnea syndrome (OSAHS). METHODS: We selected 32 children (boys: 25, 4-16 years old) who came to the hospital for diagnosing OSAHS from July to October 2016. Polysomnography (PSG) and POW were used simultaneously and recorded the apnea hypopnea index (AHI), LSpO2, and ODI4. Pearson analysis, t test, and receiver-operating characteristic (ROC) were used to analyze the correlation between PSG-AHI and other indicators, the diagnosis accordance rate, and the sensitivity and specificity of POW, respectively. RESULTS: According to PSG-AHI, 32 children were divided into two groups: primary snoring (n = 5) and OSAHS (n = 27). There was no significant difference between PSG-ODI4 and POW-ODI4 (p > .05). A statistically significant correlation between PSG-AHI and POW-ODI4 was found (r = .719, p < .001). When PSG-AHI >1, 5, 10, 15, and 20 events/h, the area under the curve (AUC) was 0.685 (p > .05), 0.733, 0.798, 0.922, and 0.929 (p < .05), respectively. There were high levels of sensitivity (83.33%) and specificity (92.31%) in the OSAHS with AHI >20 events/h level, whereas the sensitivity and specificity were unacceptable (<75%) at the level of AHI >1, 5, 10, and 15 events/h. CONCLUSIONS: POW cannot replace PSG to diagnose pediatric OSAHS because of low sensitivity and specificity, but can be used for screening severe OSAHS in children.


Assuntos
Oximetria , Polissonografia , Síndromes da Apneia do Sono/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Curva ROC , Sensibilidade e Especificidade , Ronco/diagnóstico
12.
Phytomedicine ; 45: 18-25, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29555366

RESUMO

BACKGROUND: It is well-known that the public still have been facing on a severe issue about the inconsistency of quality and therapeutic efficacy of traditional medicines. Recently, Professor Chang-Xiao Liu has created a new promising concept for identifying relevant quality-markers (Q-marker) from herbs, their formulas and manufacturing products. Therefore, building up a new approach is necessary for us to bridge over quality to efficacy of pharmaceutical products. STUDY DESIGN: In this paper, five candidate Q-markers, astragaloside IV, paeonflorin, amygdalin, tetramethylpyrazine, ferulic acid in Buyanghuanwu injection (BYHWI) had been designed to carry out in rat by using single and polypharmacokinetic models for total quanta to ascertain adequate Q-marker. METHODS: The Q-marker transitivity in vivo was studied with polypharmacokinetic model and its similarity approach, which were modeled with TQSM principle. The Q-marker was ascertained with transitive similarity and bioavailability in polypharmacokinetics. Their concentrations in plasma sample of white rat were determined by RP-HPLC. Data analyses were used by the DAS software for singles and myself-written-program with EXCEL for multiples. RESULTS: In BYHWI, five candidate Q-marker pharmacokinetic profiles were singly fixed to two compartmental models in rat using classical compartmental analysis, but there were tremendous differences among which the candidate parameters were fluctuated from nearly 3552 folds to equivalency. The theoretical value of TQSM polypharmacokinetic parameters such as AUCT, MRTT, VRTT, CLT, VT over the mixure of five drugs were 110.8 ±â€¯51.91 mg min ml-1, 176.0 ±â€¯36.5 min, 39,921 ±â€¯4311 min2, 0.3116 ±â€¯0.02347 ml min-1 kg-1, 54.83 ±â€¯7.683 ml kg-1 respectively. The TQSM polypharmacokinetic parameters in astragaloside Ⅳ ordered by AUCT, MRTT, VRTT, CLT, VT were 110.8 ±â€¯51.91 mg min ml-1, 176.0 ±â€¯36.5 min, 39,921 ±â€¯4311 min2, 0.3116 ±â€¯0.02347 ml min-1 kg-1, 54.83 ±â€¯7.683 ml kg-1, respectively, which were closed to the theoretical values. TQSM similarity versus astragaloside Ⅳ was 0.9661. CONCLUSION: The results represented that the optimum Q-marker in BYHWI is astragaloside Ⅳ, whose transitivity in vivo similarity was close to the behavior of polypharmacokinetics with maximum bioavailability to the total quanta. It is feasible for Q-marker in CMMs to screen on the comparison of single pharmacokinetic behavior and bioavailability to the total quanta.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Amigdalina/sangue , Amigdalina/farmacocinética , Animais , Disponibilidade Biológica , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/sangue , Ácidos Cumáricos/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Glucosídeos/sangue , Glucosídeos/farmacocinética , Injeções , Monoterpenos/sangue , Monoterpenos/farmacocinética , Pirazinas/sangue , Pirazinas/farmacocinética , Ratos Wistar , Saponinas/sangue , Saponinas/farmacocinética , Triterpenos/sangue , Triterpenos/farmacocinética
13.
Phytomedicine ; 45: 68-75, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29699843

RESUMO

BACKGROUND: Nowadays, to research and formulate an efficiency extraction system for Chinese herbal medicine, scientists have always been facing a great challenge for quality management, so that the transitivity of Q-markers in quantitative analysis of TCM was proposed by Prof. Liu recently. In order to improve the quality of extraction from raw medicinal materials for clinical preparations, a series of integrated mathematic models for transitivity of Q-markers in quantitative analysis of TCM were established. Buyanghuanwu decoction (BYHWD) was a commonly TCMs prescription, which was used to prevent and treat the ischemic heart and brain diseases. In this paper, we selected BYHWD as an extraction experimental subject to study the quantitative transitivity of TCM. STUDY DESIGN: Based on theory of Fick's Rule and Noyes-Whitney equation, novel kinetic models were established for extraction of active components. Meanwhile, fitting out kinetic equations of extracted models and then calculating the inherent parameters in material piece and Q-marker quantitative transfer coefficients, which were considered as indexes to evaluate transitivity of Q-markers in quantitative analysis of the extraction process of BYHWD. METHODS: HPLC was applied to screen and analyze the potential Q-markers in the extraction process. Fick's Rule and Noyes-Whitney equation were adopted for mathematically modeling extraction process. Kinetic parameters were fitted and calculated by the Statistical Program for Social Sciences 20.0 software. The transferable efficiency was described and evaluated by potential Q-markers transfer trajectory via transitivity availability AUC, extraction ratio P, and decomposition ratio D respectively. The Q-marker was identified with AUC, P, D. RESULTS: Astragaloside IV, laetrile, paeoniflorin, and ferulic acid were studied as potential Q-markers from BYHWD. The relative technologic parameters were presented by mathematic models, which could adequately illustrate the inherent properties of raw materials preparation and affection of Q-markers transitivity in equilibrium processing. AUC, P, D for potential Q-markers of AST-IV, laetrile, paeoniflorin, and FA were obtained, with the results of 289.9 mAu s, 46.24%, 22.35%; 1730 mAu s, 84.48%, 1.963%; 5600 mAu s, 70.22%, 0.4752%; 7810 mAu s, 24.29%, 4.235%, respectively. CONCLUSION: The results showed that the suitable Q-markers were laetrile and paeoniflorin in our study, which exhibited acceptable traceability and transitivity in the extraction process of TCMs. Therefore, these novel mathematic models might be developed as a new standard to control TCMs quality process from raw medicinal materials to product manufacturing.


Assuntos
Biomarcadores Farmacológicos/análise , Medicamentos de Ervas Chinesas/química , Modelos Teóricos , Amigdalina/análise , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Medicamentos de Ervas Chinesas/análise , Glucosídeos/análise , Cinética , Monoterpenos/análise , Saponinas/análise , Triterpenos/análise
14.
Phytomedicine ; 45: 36-40, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29550178

RESUMO

BACKGROUND: Drugs derived from botany have been playing essential role in both clinical treatment and pharmaceutical industry, unfortunately our worry is still that its quality and therapeutic efficacy are inconsistent. Recently many scientists launched a new project on quality (Q)-marker of medicinal herbs, this study was thus designed to generate a novel concept of quality (Q)-markers: molecular connectivity index (MCI), and to test and verify the new concept of molecular connectivity index (MCI). METHODS: The first-order term (1χ) was selected to calculate and study quality (Q)-marker for TCM. Houttuynia cordata Thunb. (HCT) was adopted as a model to verify the hypothesis. Volatile oils of HCT were determined using gas chromatography-mass (GC-MS). SIMCA 13.0 and SPSS 21.0 were used to deal with the data. RESULTS: The minimum of the MCI values was 1.273, belonging to the peak 15, but the maximum (12.822) belonged to the peak 34, and the average value of fifty volatile oils was 5.798. The results demonstrated that MCI was the principle component, and monoterpenoid and sesquiterpenoid were also the principle components in oils. Fig. 2a shows peak 5, 24, 34 were the significant ingredients, while Fig. 2b shows peak 2, 5, 24 were the significant components. CONCLUSION: The data demonstrated that MCI was associated with the structure of molecules and the therapeutic efficacy, MCI could directly exhibit the relationship between ingredients and effectiveness of Traditional Chinese Medicine (TCM). So MCI could be a potential and promising parameter for quality (Q)-marker. Therefore, MCI may be developed as a novel potential concept to control the quality of TCM.


Assuntos
Biomarcadores Farmacológicos/análise , Medicamentos de Ervas Chinesas/química , Houttuynia/química , Óleos Voláteis/análise , Biomarcadores Farmacológicos/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/normas , Cromatografia Gasosa-Espectrometria de Massas , Medicina Tradicional Chinesa/normas , Modelos Teóricos , Monoterpenos/análise , Monoterpenos/química , Óleos Voláteis/química , Plantas Medicinais/química , Controle de Qualidade , Sesquiterpenos/análise , Sesquiterpenos/química
16.
Rev Sci Instrum ; 82(5): 055116, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21639547

RESUMO

A 1.2 MV∕50 mA symmetrical Cockcroft-Walton (SCW) power supply of over 83% power efficiency, driven by 50 Hz frequency, was developed for an industrial electron beam irradiator. It is constructed by capacitors of 45 nF and 28.13 nF in the coupling column and capacitors of 18.75 nF in the smoothing column. Working status of the rectifier in high power output condition was analyzed, and the conduction angle of the rectifier was calculated. The power factor (PF) of the SCW circuit has been studied, and the equivalent condensance of the circuit has been derived. Measurements were done for the PF compensation. The surge impact during the short circuit transient process was considered in choosing the protection resistance. Test results showed that design specifications of the power supply were achieved, with the non-load voltage being up to 1.32 MV and the ratio of ripple voltage to output voltage as 9.4%.

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