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1.
Pharmeur Bio Sci Notes ; 2021: 1-25, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33734082

RESUMEN

Following a decision of the European Pharmacopoeia (Ph. Eur.) Commission, the Traditional Chinese Medicines (TCM) Working Party started a pilot phase to examine the suitability of a high-performance thin-layer chromatography (HPTLC) minimum content test as an alternative to the classical assay in TCM monographs. This approach was evaluated with two TCM herbal drugs: Fritillaria thunbergii bulbs (FTB) and Corydalis rhizome (CYR). Firstly, the existing HPTLC methods were optimised for both drugs. The new methods were applied to the evaluation of multiple samples, and acceptance criteria for the identification, following Ph. Eur. chapter 2.8.25. High-performance thin-layer chromatography of herbal drugs and herbal drug preparations, were set. The HPTLC test for minimum content of markers was then developed and validated. In this test, the intensity of the marker zone in the fingerprint of the sample is compared to the corresponding zone in the reference solution, which has a concentration giving an intensity equivalent to the acceptance criterion. This test gives a pass or fail result rather than a content and can be performed visually (on the images) or by software (using peak profiles from images; PPI). Reproducibility of the HPTLC methods was evaluated in a collaborative trial including six laboratories. In summary, results for FTB from five laboratories were in agreement. The remaining laboratory did not pass the identification of the samples. For CYR, all laboratories presented the same results for identification. In the test for minimum content, one borderline sample passed in four laboratories and failed in two. All laboratories reached similar conclusions for the other seven samples. The HPTLC methods proposed offer a simplified approach to evaluating identity and minimum content of TCM drugs in a single analysis.


Asunto(s)
Fritillaria , Preparaciones Farmacéuticas , Cromatografía en Capa Delgada , Medicina Tradicional China , Reproducibilidad de los Resultados
2.
Phytomedicine ; 58: 152855, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30851581

RESUMEN

BACKGROUND: The Tripterygium glycosides (TG) is the main active extractive of Tripterygium wilfordii Hook F and is widely used in clinical practice to treat inflammatory diseases (including inflammatory bowel disease). However, due to its severe toxicity, TG is restricted to the treatment of many diseases. Therefore, it is necessary to study a new method to obtain the attenuated and synergistic extracts from TG. PURPOSE: Tripterygium glycosides-n2 (TG-n2) was obtained from TG by a new preparation method. In this study, we aimed to investigate the difference in the chemical compositions between TG and TG-n2, further explored its toxicity and therapeutic effects on DSS-induced colitis in mice. METHODS: The major chemical compositions of TG and TG-n2 were analyzed by ultra-performance liquid chromatography (UPLC). Subsequently, acute toxicity test was applied to evaluate the toxicity difference between TG and TG-n2. Dextran sulfate sodium (DSS)-induced acute colitis model was used to explore the therapeutic effect of TG and TG-n2 and their potential mechanisms of action. RESULTS: We found that the chemical compositions of TG-n2 is different from TG. The main difference is the ratio of triptriolide (T11) / triptolide (T9). Acute toxicity test proved that TG-n2 was less toxic than TG. Base on this, further studies showed that TG-n2 has a similar therapeutic effect as compared to TG on attenuating the symptoms of colitis, such as diarrhea, bloody stools, body weight loss, colonic atrophy, histopathological changes, inhibiting cytokines secretion and reducing absolute lymph number. In addition, TG and TG-n2 can increase the apoptosis of T lymphocyte in vivo. Further investigated showed that TG and TG-n2 could increase the expressions of Bax and p62 on CD3-positive T cells. CONCLUSION: This study showed that oral administration of TG-n2 is safer than TG. Moreover, the attenuated TG-n2 has the similar therapeutic effect on treating experimental colitis in mice when compared to TG. Its mechanism may be related to activating the expression of Bax in T cells and inducing T cells autophagy to regulate the survival of T lymphocytes in colitis mice, thus reducing inflammation in colon.


Asunto(s)
Colitis/tratamiento farmacológico , Glicósidos/farmacología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Tripterygium/química , Animales , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Colitis/inducido químicamente , Colon/efectos de los fármacos , Colon/patología , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Glicósidos/química , Glicósidos/aislamiento & purificación , Glicósidos/toxicidad , Homeostasis , Inflamación/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos BALB C , Linfocitos T/efectos de los fármacos
3.
Phytomedicine ; 17(8-9): 606-13, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20092987

RESUMEN

To elucidate the cytotoxicity mechanism of Ganoderma triterpenes, a chemoproteomic study using five purified ganoderic acids, ganoderic acid F (GAF), ganoderic acid K (GAK), ganoderic B (GAB), ganoderic acid D (GAD) and ganoderic acid AM1 (GAAM1) was conducted. GAF, GAK, GAB, GAD and GAAM1 treatment for 48 h inhibited the proliferation of HeLa human cervical carcinoma cells with IC(50) values of 19.5+/-0.6 microM, 15.1+/-0.5 microM, 20.3+/-0.4 microM, 17.3+/-0.3 microM, 19.8+/-0.7 microM, respectively. The protein expression profiles of HeLa cells treated with each ganoderic acid at dose of 15 microM for 48 h were checked using two-dimensional electrophoresis (2-DE). The possible target-related proteins of ganoderic acids, i.e. proteins with same change tendency in all five ganoderic acids-treated groups compared with control, were identified using MALDI-TOF MS/MS. Twelve proteins including human interleukin-17E, eukaryotic translation initiation factor 5A (eIF5A), peroxiredoxin 2, ubiquilin 2, Cu/Zn-superoxide dismutase, 14-3-3 beta/alpha, TPM4-ALK fusion oncoprotein type 2, PP2A subunit A PR65-alpha isoform, nucleobindin-1, heterogeneous nuclear ribonucleoprotein K, reticulocalbin 1 and chain A of DJ-1 protein were identified. Ganoderic acids might exert their cytotoxicity by altering proteins involved in cell proliferation and/or cell death, carcinogenosis, oxidative stress, calcium signaling and ER stress.


Asunto(s)
Antineoplásicos/farmacología , Productos Biológicos/farmacología , Carcinoma/metabolismo , Proteoma/efectos de los fármacos , Reishi/química , Triterpenos/farmacología , Neoplasias del Cuello Uterino/metabolismo , Antineoplásicos/uso terapéutico , Productos Biológicos/uso terapéutico , Carcinoma/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Electroforesis , Femenino , Células HeLa , Ácidos Heptanoicos/farmacología , Ácidos Heptanoicos/uso terapéutico , Humanos , Concentración 50 Inhibidora , Fitoterapia , Proteínas/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Triterpenos/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico
4.
J Asian Nat Prod Res ; 8(8): 713-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17145659

RESUMEN

Biotransformation of dehydrocostuslactone (1) by Mucor polymorphosporus yielded four compounds, and their structures were identified as 11alpha,13-dihydrodehydrocostuslactone (2), 3alpha-hydroxy-11alpha,13-dihydrodehydrocostuslactone (3), 3beta-hydroxy-4beta,15,11alpha,13-tetrahydrodehydrocostuslactone (4) and 2beta-hydroxyl-11alpha,13-dihydrodehydrocostuslactone (5), respectively, on the basis of their spectral data. Among them, compound 5 is a new compound.


Asunto(s)
Asteraceae/química , Lactonas/química , Lactonas/metabolismo , Mucor/metabolismo , Plantas Medicinales/metabolismo , Sesquiterpenos/metabolismo , Biotransformación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Especificidad de la Especie , Espectrofotometría
5.
Chemotherapy ; 48(6): 303-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12673105

RESUMEN

BACKGROUND: The fruit extract of Gleditsia sinensis Lam. (GSE) is a traditional herbal medicine that is saponin-rich. However, its activity on solid tumour cell lines has never been demonstrated. METHODS: The activity of GSE was demonstrated in four cancer cell lines (breast cancer MCF-7, MDA-MB231, hepatoblastoma HepG2 and oesophageal squamous carcinoma cell line SLMT-1) using MTT assay, anchorage-independent clonogenicity assay, DNA laddering and in situ cell death detection. RESULTS: The mean MTT(50) (the mean concentration of GSE to reduce MTT activity by 50%) ranged from 16 to 20 microg/ml of GSE. An anchorage-independent clonogenicity assay showed that all of the four solid tumour cell lines gradually lost their regeneration potential after treatment with GSE, DNA fragmentation and TUNEL analysis demonstrated that the action of GSE is both dose- and time course-dependent. CONCLUSIONS: Our results suggest that GSE has a cytotoxic activity and can induce apoptosis in human solid tumour cell lines.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Gleditsia/química , Apoptosis , División Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Frutas , Humanos , Extractos Vegetales/farmacología , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
6.
J Asian Nat Prod Res ; 3(3): 229-33, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11491399

RESUMEN

A new phenolic glycoside, 4-propionyl-2,6-dimethoxyphenyl beta-D-glucopyranoside (1) and a new trans-clerodane diterpene named 19-deacetylconyzalactone (2), were isolated from the aerial parts of Conyza blinii.


Asunto(s)
Asteraceae/química , Diterpenos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Cromatografía , Diterpenos/química , Glicósidos/química , Medicina Tradicional China , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Plantas Medicinales/química , Espectrofotometría Infrarroja , Estereoisomerismo
7.
Zhongguo Zhong Yao Za Zhi ; 26(8): 551-3, 2001 Aug.
Artículo en Chino | MEDLINE | ID: mdl-12776370

RESUMEN

OBJECTIVE: Study on the non-anthraquinone constituents from rhizoma and radix of Rheum sublanceolatum. METHOD: The constituents were isolated through column chromatography and identified on the basis of their physiochemical and spectral data. RESULT: Six non-anthraquinone constituents were isolated and identified as n-octacosanic acid, sitosterol, daucosterol, 2-methyl-5-carboxymethyl-7-hydroxychromone, piceatannol and 6-hydroxymusizin-8-O-beta-D-glucopyranoside. CONCLUSION: All these compounds were firstly isolated from R. sublanceolatum.


Asunto(s)
Plantas Medicinales/química , Rheum/química , Sitoesteroles/aislamiento & purificación , Estilbenos/aislamiento & purificación , Raíces de Plantas/química , Rizoma/química , Sitoesteroles/química , Estilbenos/química
8.
Yao Xue Xue Bao ; 35(11): 860-3, 2000 Nov.
Artículo en Chino | MEDLINE | ID: mdl-11218867

RESUMEN

AIM: To investigate the antifungal effect of three natural products on the genetic substance of Saccharomyces cerevisiae GL7 and Prototheca wickerhamii. METHODS: The normal and treated cells were observed by confocal laser scanning microscope (CLSM) and image analysis to quantitatively described the cell morphology, area, DNA and RNA content. RESULTS: The morphology, area, DNA and RNA contents were changed greatly in the treated cells. CONCLUSION: Solasodine, 4'-hydroxy-3, 5-dimethoxystilbene and dictamnine directly or indirectly interfered the synthesis and function of genetic substance in S. cerevisiae and P. wickerhamii.


Asunto(s)
Antifúngicos/farmacología , ADN de Hongos/efectos de los fármacos , Prototheca/efectos de los fármacos , Quinolinas , ARN de Hongos/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Alcaloides/farmacología , Prototheca/genética , Saccharomyces cerevisiae/genética , Alcaloides Solanáceos/farmacología
9.
J Asian Nat Prod Res ; 2(1): 39-44, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-11261204

RESUMEN

Incubation of 24 alpha- and 24 beta-methylcholesterols with yeast mutant GL7 afforded their corresponding C-22-desaturated products under the catalysis of sterol delta 22(23)-desaturase. The metabolites were identified to be 22-dehydro-24 alpha-methylcholesterol (2% yield from 24 alpha-methylcholesterol) and 22-dehydro-24 beta-methylcholesterol (51% yield from 24 beta-methylcholesterol) respectively on the basis of their chromatographic and spectral properties. It was concluded that the sterol delta 22(23)-desaturase prefers the 24 beta-methyl sterols and is highly stereospecific.


Asunto(s)
Colesterol/análogos & derivados , Colesterol/farmacocinética , Mutación , Fitosteroles , Saccharomyces cerevisiae/metabolismo , Biotransformación , Colesterol/química , Cromatografía Líquida de Alta Presión , Isomerismo , Espectroscopía de Resonancia Magnética , Saccharomyces cerevisiae/genética
10.
J Asian Nat Prod Res ; 1(4): 313-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-11523552

RESUMEN

A triterpenoid saponin (1) was obtained from the stem barks of Albizia julibrissin Durazz. Its structure was elucidated as 3-O-[beta-D-xylopyranosyl-(1 --> 2)-alpha-L-arabinopyranosyl-(1 --> 6)-beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-beta-D-quinovopyranosyl-2, 7-octadienoyl]-16-deoxy-acacic acid 28-O-beta-D-glucopyranosyl-(1 --> 3)-[alpha-L-arabinofuranosyl-(1 --> 4)]-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl ester (1), named as Julibroside J26, based on the chemical and spectral methods.


Asunto(s)
Monoterpenos , Rosales/química , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Secuencia de Carbohidratos , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Modelos Químicos , Datos de Secuencia Molecular , Tallos de la Planta/química , Saponinas/química , Espectrometría de Masa Bombardeada por Átomos Veloces , Triterpenos/química
11.
J Asian Nat Prod Res ; 1(2): 99-102, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-11261220

RESUMEN

Biotransformation of podophyllotoxin (PT) by several microbial species has been investigated. Among the fungi tested, it was found that Penicillium strains can isomerize PT to picropodophyllin (PPT) in 8% yield and other strains also transform the substrate into the same product but with lower yield.


Asunto(s)
Penicillium/metabolismo , Podofilotoxina/metabolismo , Podofilotoxina/farmacocinética , Biotransformación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Podofilotoxina/análogos & derivados , Podofilotoxina/química
12.
Yao Xue Xue Bao ; 32(4): 282-5, 1997 Apr.
Artículo en Chino | MEDLINE | ID: mdl-11499031

RESUMEN

Eight compounds were isolated from the aerial parts of Siegesbeckia orientalis L. and their structures were elucidated by spectroscopic methods(IR, EI-MS, 13C-NMR, 1H-NMR, 1H-1H COSY, 1H-1H NOESY and 1H-13C COSY). Compounds I and II are new natural products and named siegesesteric acid(I) and siegesetheric acid(II), their structures were confirmed as ent-17-acetoxy-18-isobutyryloxy-16(alpha)-kauran-19-oic acid(I) and ent-17-ethoxy-16(alpha)-(-)-kauran-19-oic acid(II). The others were identified as known compounds: ent-16 beta, 17-dihydroxy-kauran-19-oic acid (III), kirenol(IV), beta-sitosteryl glucoside(V), heneicosanol(VI), methyl arachidate(VII) and beta-sitosterol(VIII). These compounds, except kirenol and beta-sitosterol, were isolated for the first time from the title plant.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Diterpenos/aislamiento & purificación , Furanos/aislamiento & purificación , Lactonas/aislamiento & purificación , Plantas Medicinales/química , Antineoplásicos Fitogénicos/química , Diterpenos/química , Furanos/química , Lactonas/química , Magnoliopsida/química , Conformación Molecular
13.
Subcell Biochem ; 28: 89-116, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9090292

RESUMEN

During the course of the last decade, the development of SBIs, and particularly sterol biomethylation inhibitors, has been based on the rational design approach. Successful though this approach has been in elucidating sterol biomethylation enzymology, its limitations are becoming apparent from the findings that: (i) 24,25-double bond metabolism gives rise to cholesterol and ergosterol in a mechanistically similar manner, (ii) 25-azasterols are harmful to human physiology, and (iii) side-chain modified sterols designed to inhibit the SMT enzyme in S. cerevisiae may be ineffective or operate by another kinetic mechanism in a related organism, rendering it therapeutically nonuseful. Nevertheless, it may be possible to ultimately capitalize on the unique aspects of sterol biomethylation chemistry and enzymology to design taxa-specific inhibitors. With increased understanding of the structure and function of SMT enzymes in different fungi, it should be possible to prepare novel mechanism-based inactivators to control SMT activity uniquely and with high specific activity.


Asunto(s)
Antifúngicos/farmacología , Hongos/metabolismo , Esteroles/biosíntesis , Secuencia de Aminoácidos , Antifúngicos/química , Arabidopsis/enzimología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Hongos/efectos de los fármacos , Metilación/efectos de los fármacos , Metiltransferasas/antagonistas & inhibidores , Metiltransferasas/metabolismo , Datos de Secuencia Molecular , Estructura Molecular , Saccharomyces/enzimología , Homología de Secuencia de Aminoácido
14.
Lipids ; 31(4): 373-7, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8743048

RESUMEN

The ERG6 gene from Saccharomyces cerevisiae has been functionally expressed in Escherichia coli, for the first time, yielding a protein that catalyzes the bisubstrate transfer reaction whereby the reactive methyl group from (S)-adenosyl-L-methionine is transferred stereoselectively to C-24 of the sterol side chain. The structural requirements of sterol in binding and catalysis were similar to the native protein from S. cerevisiae. Inhibition of biomethylation was observed with fecosterol and ergosterol which suggests that ergosterol may function in wild-type yeast as feedback regulator of sterol biosynthesis.


Asunto(s)
Metiltransferasas/metabolismo , Saccharomyces cerevisiae/enzimología , Esteroles/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Catálisis , Cromatografía Líquida de Alta Presión , Clonación Molecular , Escherichia coli/metabolismo , Genes Fúngicos , Cinética , Metiltransferasas/biosíntesis , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Plásmidos , ARN Mensajero/biosíntesis , ARN Mensajero/química , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Mapeo Restrictivo , Saccharomyces cerevisiae/genética , Especificidad por Sustrato
15.
Biochim Biophys Acta ; 1299(3): 313-24, 1996 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-8597586

RESUMEN

The mechanism of action and active site of the enzyme (S)-adenosyl-L-methionine:delta 24(25)-sterol methyl transferase (SMT) from Saccharomyces cerevisiae strain GL7 have been probed with AdoMet, (S)-adenosyl-L-homocysteine, a series of 35 sterol substrates as acceptor molecules and a series of 10 substrate and high energy intermediate (HEI) sterol analogues as inhibitors of biomethylation. The SMT was found to be selective for sterol, both regio- and stereochemically. The presence of an unhindered 24,25-bond, an equatorially-oriented polar group at C-3 (which must act as a proton acceptor) attached to a planar nucleus and a freely rotating side chain were obligatory structural features for sterol binding/catalysis; no essential requirement or significant harmful effects could be found for the introduction of an 8(9)-bond, 14 alpha-methyl or 9 beta,19-cyclopropyl group. Alternatively, methyl groups at C-4 prevented productive sterol binding to the SMT. Initial velocity, product inhibition, and dead-end experiments demonstrated a rapid-equilibrium random bi bi mechanism. Deuterium isotope effects developed from SMT assays containing mixtures of [3-3H]zymosterol with AdoMet or [methyl-2H3]AdoMet confirmed the operation of a random mechanism, kappa H/kappa D = 1.3. From this combination of results, the spatial relationship of the sterol substrate to AdoMet could be approximated and the topology of the sterol binding to the SMT thereby formulated.


Asunto(s)
Metiltransferasas/metabolismo , S-Adenosilmetionina/metabolismo , Saccharomyces cerevisiae/enzimología , Esteroles/metabolismo , Fraccionamiento Celular , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos , Cinética , Metilación , Metiltransferasas/antagonistas & inhibidores , Microsomas/enzimología , Modelos Biológicos , Solubilidad , Especificidad por Sustrato
16.
Lipids ; 30(3): 203-19, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7791528

RESUMEN

Sixty-one sterols and pentacyclic triterpenes have been isolated and characterized by chromatographic and spectral methods from Zea mays (corn). Several plant parts were examined; seed, pollen, cultured hypocotyl cells, roots, coleoptiles (sheaths), and blades. By studying reaction pathways and mechanisms on plants fed radiotracers ([2-(14)C]mevalonic acid, [2-(14)C]acetate, and [2-(3)H]acetate), and stable isotopes (D2O), we discovered that hydroxymethylgutaryl CoA reductase is not "the" rate-limiting enzyme of sitosterol production. Additionally, we observed an ontogenetic shift and kinetic isotope effect in sterol biosynthesis that was associated with the C-24 alkylation of the sterol side chain. Blades synthesized mainly 24 alpha-ethyl-sterols, sheaths synthesized mainly 24-methyl-sterols, pollen possessed an interrupted sterol pathway, accumulating 24(28)-methylene-sterols, and germinating seeds were found to lack an active de novo pathway. Shoots, normally synthesizing (Z)-24(28)-ethylidine-cholesterol, after incubation with deuterated water, synthesized the rearranged double-bond isomer, stigmasta-5,23-dien-3 beta-ol. Examination of the mass spectrum and 1H nuclear magnetic resonance spectrum of the deuterated 24-ethyl-sterol indicated the Bloch-Cornforth route originating with acetyl-CoA and passing through mevalonic acid to sterol was not operative at this stage of development. An alternate pathway giving rise to sterols is proposed.


Asunto(s)
Fitosteroles/biosíntesis , Zea mays/metabolismo , Acetatos/metabolismo , Alquilación , Radioisótopos de Carbono , Cromatografía Líquida de Alta Presión , Hidroximetilglutaril-CoA Reductasas/metabolismo , Espectrometría de Masas , Ácido Mevalónico/metabolismo , Modelos Biológicos , Oxidación-Reducción , Fitosteroles/análisis , Fitosteroles/química , Raíces de Plantas/química , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Brotes de la Planta/química , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Semillas/química , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Sitoesteroles/metabolismo , Distribución Tisular , Zea mays/química , Zea mays/crecimiento & desarrollo
17.
Zhongguo Zhong Yao Za Zhi ; 19(2): 100-1, 127, 1994 Feb.
Artículo en Chino | MEDLINE | ID: mdl-8011129

RESUMEN

The volatile oil obtained from Echinops grijisii roots was analysed by GC-MS method. Twenty four constituents have been identified from the oil, among which cis-beta-farnesene and 5-(3-buten-1-ynyl)bithiophene are the main ones.


Asunto(s)
Medicamentos Herbarios Chinos/química , Aceites Volátiles/química , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/aislamiento & purificación
18.
Yao Xue Xue Bao ; 26(6): 442-6, 1991.
Artículo en Chino | MEDLINE | ID: mdl-1789111

RESUMEN

Three phytoecdysteroids I, II and III were isolated from the root of Rhaponticum uniflorum (L.) DC. and their structures were elucidated by chemical and spectroscopic methods (UV, IR, EI-MS, FAB-MS, 1HNMR, 13CNMR, 1H-1H COSY, 1H-1H NOESY, 1H-13CCOSY and CD). Compound II is new and named rhapontisterone, its structure was confirmed as (20R, 22R, 24S)-2 beta, 3 beta, 11 alpha, 14 alpha, 20, 22, 24-heptahydroxy-5 beta cholest-7-en-6-one. The other two, I and III, were identified as ecdysterone and turkesterone, respectively, both are known compounds, but turkesterone was isolated for the first time from the title plant.


Asunto(s)
Medicamentos Herbarios Chinos/química , Ecdisterona/análogos & derivados , Ecdisterona/aislamiento & purificación
19.
Chin Med J (Engl) ; 102(6): 449-52, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2512067

RESUMEN

Of ninety-eight patients with intracranial tumors examined by dynamic CT scanning, 66 were confirmed operatively and pathologically. Our study showed that: 1) Dynamic CT can be performed safely and easily in outpatients; 2) Acoustic neurinoma, meningioma, pituitary chromophobe adenoma, astrocytoma and metastatic tumor have varying levels of time-density curves; 3) The tissue-blood ratio (TBR) at peak time (TBRp) is a useful indicator of the vascularity of tumoral tissues, and analysis of the time-density curve combining with TBRp is helpful to the differential diagnosis of tumors; 4) Differential diagnosis between tumors and vascular abnormalities such as aneurysm and arteriovenous malformation could be made easily with dynamic CT.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adenoma Cromófobo/diagnóstico por imagen , Adolescente , Adulto , Anciano , Astrocitoma/diagnóstico por imagen , Femenino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Persona de Mediana Edad , Neoplasias Hipofisarias/diagnóstico por imagen
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