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1.
J Org Chem ; 82(16): 8598-8603, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28727454

RESUMO

Under rhodium(III) catalysis, four kinds of cycloalkenecarboxylic acids successfully reacted with acrylates via direct activation of the ß-alkenyl C-H bond. The present protocol provides the facile and highly efficient synthesis of substituted furan-2(5H)-ones from readily available starting materials with moderate to good yields. In addition, their possible reaction mechanisms were also discussed.

2.
Yao Xue Xue Bao ; 48(12): 1807-11, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24689238

RESUMO

How to identify active constituents of traditional Chinese medicines (TCMs) and study their interactions are key problems in the development of TCMs. The inhibitory effect of six alkaloids from Rhizoma Coptidis (RC) on Shigella dysenteriae (S. dysenteria) growth had been investigated by microcalorimetry in this study. Main active constituents of RC were confirmed by comparing their contributions to the bacteriostatic effect, and the interactions among active constituents were further researched. According to the result, in 0.8 mg-mL-1 extract of RC, the contributions of six active alkaloids including berberine, coptisine, epiberberine, palmatine and the combination of jatrorrhizine and columbamine were 52.83%, 36.31%, 2.49%, 4.27% and 3.21%, respectively. Therefore, berberine and coptisine were the main active constituents of RC that inhibited the growth of S. dysenteria. The study of interactions among the six alkaloids indicated that, 1 there were some contstituents antagonizing the inhibitory effect of RC, 2 there was a synergy effect between berberine and coptisine, 3 there were additive effects between other four alkaloids and the main active constituents. These results may provide some useful references for the establishment of the quality standard for RC and the development of multi-component TCMs.


Assuntos
Alcaloides/farmacologia , Berberina/análogos & derivados , Berberina/farmacologia , Coptis/química , Alcaloides/análise , Berberina/análise , Alcaloides de Berberina/análise , Alcaloides de Berberina/farmacologia , Interações Medicamentosas , Sinergismo Farmacológico , Plantas Medicinais/química , Controle de Qualidade , Rizoma/química , Shigella dysenteriae/efeitos dos fármacos , Shigella dysenteriae/crescimento & desenvolvimento
3.
Zhongguo Zhong Yao Za Zhi ; 37(17): 2672-5, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23236775

RESUMO

For a long time, due to the shortage of a objective and clear method and standard for the quality evaluation of the Dao-di herb, it is difficult to distinguish the Dao-di herb. Geo-herbalism and environment-related studies often fall into the vicious circle of "have target but no indicators" and "circular reasoning" because of lack of objective and a clear indication of the quality characteristics. So it is difficult to reveal the ecological environment factors that form the quality of Dao-di herb. The research team put forward innovative idea that taking the medicine quality evaluation method and authentic standard as a breakthrough, starting from the effect, evaluating quality by effect, evaluating the environment by the drug quality, and establishing the thinking and pattern of identify authentic Chinese herbs (quality ecological studies of the Dao-di herb) based on the research path of "effect-quality-environment". The authors hope that they can provide theoretical and technical support to reveal the dominant factors of the ecological environment that impact of the quality of the Dao-di herb, build the Dao-di herb clinical application of dose conversion mechanism, clarify the connotations of the modern science of the Dao-di herb and solve the key issues that constraint the development of the Dao-di herb production and clinical application of it.


Assuntos
Medicamentos de Ervas Chinesas/normas , Ecossistema , Medicina Herbária/normas , Plantas Medicinais/química , Medicamentos de Ervas Chinesas/análise , Plantas Medicinais/genética , Controle de Qualidade
4.
Diagnostics (Basel) ; 12(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35453994

RESUMO

Differentiating tumor tissue from dense breast tissue can be difficult. Dual-energy CT (DECT) could be suitable for making diagnoses at breast cancer follow-ups. This study investigated the contrast in DECT images and iodine maps for patients with breast cancer being followed-up. Chest CT images captured in 2019 were collected. Five cases of metastatic breast cancer in the lungs were analyzed; the contrast-to-noise ratio (for breast tissue and muscle: CNRb and CNRm, respectively), tumor-to-breast mammary gland ratio (T/B), and tumor-to-muscle ratio (T/M) were calculated. For 84 cases of no metastasis, monochromatic spectral and iodine maps were obtained to compare differences under various breast densities using the K-means algorithm. The optimal T/B, T/M, and CNRb (related to mammary glands) were achieved for the 40-keV image. Conversely, CNRm (related to lungs) was better for higher energy. The optimal balance was achieved at 80 keV. T/B, T/M, and CNR were excellent for iodine maps, particularly for density > 25%. In conclusion, energy of 80 keV is the parameter most suitable for observing the breast and lungs simultaneously by using monochromatic spectral images. Adding iodine mapping can be appropriate when a patient's breast density is greater than 25%.

5.
ACS Omega ; 6(50): 34606-34614, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34963945

RESUMO

Organometal halide perovskites are highly promising materials for photovoltaic applications due to the rapid growth of power conversion efficiency in recent years. However, thermal stability is still a major hurdle for perovskite solar cells toward commercialization. Herein, we first explore the slow thermal response of the CH3NH3PbI3 perovskite crystal investigated via Auger electron spectroscopy (AES). AES image mapping directly observes the evolution of morphology and elemental distribution over time. The AES small spot analysis demonstrates the precise initial degradation position of perovskite with both information regarding physical changes in crystals and chemical changes in elemental bonding at the nanometer scale. X-ray photoelectron spectroscopy (XPS) was used to confirm the surface chemical bonding and composition of the perovskite crystals. This work provides the first insights into the physical and chemical changes of perovskites investigated by AES upon long-term exposure to heat under ambient conditions.

6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): o211, 2009 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-21580096

RESUMO

In the title compound, C(30)H(39)OP, the P=O bond length is 1.4866 (12) Šand the P-C bond lengths range from 1.804 (2) to 1.808 (13) Å. The molecle is located on a crystallographic mirror plane. The methyl groups of one tert-butyl group are disordered over two sites in a 0.776 (4):0.224 (4) ratio.

7.
Pest Manag Sci ; 74(3): 579-589, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28941309

RESUMO

BACKGROUND: Herbicides that inhibit 4-hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) are very important for grass weed control. In order to discover novel HPPD herbicides, a series of triketone 2H-benzo[b] oxazin-3(4H)-one analogs was designed and synthesized. RESULTS: In comparison with the commercial triketone HPPD herbicide mesotrione (IC50 = 0.252 µM), some of these new triketone analogs displayed excellent HPPD inhibitory potency in vitro, for example B39 (IC50 = 0.172 µM) and B41 (IC50 = 0.156 µM). In addition, some of these compounds exhibited pre- and post-emergence herbicidal activity similar to mesotrione when applied at 375 g/ha. CONCLUSION: Many of the title compounds described in this paper could be important lead structures for the further development of novel HPPD herbicides. © 2017 Society of Chemical Industry.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Benzoxazinas/farmacologia , Cicloexanonas/farmacologia , Herbicidas/farmacologia , Controle de Plantas Daninhas , Estrutura Molecular , Relação Estrutura-Atividade
8.
Zhongguo Zhen Jiu ; 34(11): 1077-80, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25675566

RESUMO

OBJECTIVE: To compare the difference in clinical efficacy on lumber disc herniation (LDH) treated with Yaoyangguan (GV 3) between mild moxibustion under thermosensitive condition and that under non-thermo-sensitive condition. METHODS: Fifty-seven LDH patients were selected as the study objects. Mild moxibustion at Yaoyangguan (GV 3) was applied for 45 min each time. Additionally, the conventional acupuncture was given, once a day, for 20 days. At the end of treatment, two groups were classified. A thermosensitive acupoint group (thermosensitive group) was composed of the cases with thermo-sensitization at Yaoyangguan (GV 3) and presenting for > or =4 times in the entire treatment. A non-thermosensitive acupoint group (tranquilization group) was composed of the cases without thermo-sensitization or the frequency of thermo-sensitization <4 times in the entire treatment. The modified Japanese orthopedics association scoring system (M-JOA) was adopted to observe the cases before and after treatment and 6 months after treatment in the two groups. The efficacy was compared between the two groups. RESULTS: After treatment and in 6 months after treatment, the score of M-JOA was apparently reduced as compared with that before treatment in the two groups (all P<0.05). The score reducing in the thermosensitization group was more obvious than that in the tranquilization group (both P<0.01). After treatment and in 6 months after treatment, the curative rate and remarkably effective rate were 89.7% (26/29) and 79.3% (23/29), which was better than 71.4% (20/28) and 60.7% (17/28, both P<0.05) in the tranquilization group separately. CONCLUSION: Mild moxibustion at acupoint under thermosensitive condition achieves the better short-term and long-term effects as compared with that under non-thermosensitive condition.


Assuntos
Pontos de Acupuntura , Deslocamento do Disco Intervertebral/terapia , Moxibustão , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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