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Biomedical subjects

Q S Zhao

Publications and source records attributed to Q S Zhao.

12 recordsLinked to original sources
PubMed2001

Cytotoxic 7,20-epoxy ent-kauranoids from Isodon xerophilus.

Four 7,20-epoxy ent-kaurane diterpenoids, xerophilusins G (1) and I-K (2-4), were isolated from the leaves of Isodon xerophilus, along with four known ones, enanderianin C (5), rosthorin A (6), longikaurin B (7), and rabdoternin D (8). Their structures were determined primarily using NMR spectroscopic techniques. The structure and stereochemistry of 3 were confirmed by X-ray crystallography. Compounds 4 and 7 exhibited broad cytotoxicity against four kinds of human tumor cells (K562, HL-60, HCT, and MKN-28 cells) in the range of 2.23-15.35 and 0.30-8.61 microg/ml, respectively.

Antineoplastic Agents, Phytogenic↗
PubMed2001

[The development of an all-purpose medical electronic teaching instrument].

This paper introduces a kind of all-purpose medical electronic teaching instrument. According to the modularization design rule, a medical electronic teaching instrument integrated with information transfer, signal processing, keyboard monitoring and signal sampling, etc, can be realized. On the other hand, A/D, D/A, self-detecting of computer, collecting and testing of biological potentials, driving electromotor and generating functional signals, etc can also be realized by the related software based on the system. It has been proved that, by using single-chip processor and computer, the system can implement full-scale test and processing of biomedical signals so that operators can understand the principles and the construction of medical instruments more easily and deeply. Therefore, it is valuable in application of medical electronic coursesteaching, research and etc.

Computer-Assisted Instruction↗
PubMed2000

Diterpenoids from Isodon lophanthoides.

A new diterpenoid was isolated from the leaves of Isodon lophanthoides, together with two known diterpenoids, lophanic acid and 8(17),12,14-labdatriene-19-oic acid. The structure of the new compound was determined to be 11 beta-hydroxyisopimara-8,15-diene-3-one (1) on the basis of spectroscopic evidence.

Diterpenes↗
PubMed2000

A new ent-kaurane diterpenoid from Isodon phyllostachys.

A new ent-kaurane diterpenoid, phyllostachysin C (1), together with five known compounds, sculponeatins B and C, nodosin, ursolic acid and 2 alpha-hydroxyursolic acid, were isolated from the leaves of Isodon phyllostachys. The structure of 1 was elucidated on the basis of its spectral properties.

Diterpenes↗
PubMed2000

Structures of two diterpenoid dimers from bulbs of Fritillaria ebeiensis.

A new ent-kaurane diterpenoid dimer, fritillebinide C(1) together with one known diterpenoid dimer fritillebinide B (2) were isolated from the bulbs of Fritillaria ebeiensis G.D. Yu et G.Q. Ji. Compound 1 has been determined to be ent-3beta-acetoxy-kauran-16beta,17-acetal ent-16beta-kauran-17(S)-aldehyde(1) by means of spectral analysis and chemical evidence.

Chromatography↗
PubMed2000

Structural elucidations of two ent-kaurane dimers from bulbs of Fritillaria ebeiensis var. purpurea.

A novel ent-kaurane diterpenoid dimer, fritillebinide B (1) together with one known diterpenoid dimer fritillebinide A (2) were isolated from the bulbs of Fritillaria eheiensis var. purpurea G.D. Yu et P. Li. Compound 1 has been established to be ent-3beta-acetoxy-kauran-16beta,17-acetal ent-16beta-kauran-17(R)-aldehyde (1) by means of spectral analysis and chemical evidence.

Chromatography↗
PubMed2000

[HSP70 expression of middle ear mucosa in acute suppurative otitis media].

OBJECTIVE: To study HSP70 expression of middle ear mucosa in acute suppurative otitis media. METHOD: An animal model of acute middle ear infection was established by inoculating Klebsiella Pneumoniae into middle ear of guinea pigs. Animals were sacrificed 1, 3, 5 and 7 days after inoculation. The expression of Hsp70 epitope related proteins in middle ear mucosa were analysed by modified western blot test. RESULT: Very light 70 kD bands were recognized by anti Hsp70 monoclonal antibody in the unstressed group. However, middle ear mucosa of the stressed group not only showed relatively strong 70 kD bands, but also expressed more intensely 31 kD and 17 kD bands. The infected mucosa expressed one 70 kD band at 1st day, the strongest band at 3rd day, falling at 5th day; 31 kD was recognized two bands at 3rd day, the strongest bands at 5th day, falling at 7th day; two bands of 17 kD were detected in all days, with the strongest bands at 7th day. CONCLUSION: The results suggested that middle ear mucosa expressed Hsp70 and Hsp70 epitope related proteins like 31 kD and 17 kD in acute otitis media.

Animals↗
PubMed1999

ent-kaurane diterpenoids from Isodon lungshengensis.

Six new ent-kaurane diterpenoids, lungshengenins B-G (1-6), together with three known diterpenoids, lungshengenin A (7), inflexin (8), and lushanrubescinsin C (9), were isolated from the leaves and tender branches of Isodon lungshengensis. Their structures were elucidated by means of spectroscopy, mainly 1D and 2D NMR techniques. Lungshengenins A (7), C (2), and G (6) were cytotoxic toward K562 cells, having IC(50) values equal to or less than 10 microg/mL.

Antineoplastic Agents, Phytogenic↗
PubMed1999

Structures of two new diterpenoid dimers from bulbs of Fritillaria ebeiensis.

Two new ent-kauranoid diterpenoid dimers, fritillebin C (1) and fritillebin D (2), were isolated from the bulbs of Fritillaria ebeiensis G.D. Yu and G.Q. Ji. Their structures were determined to be ent-16beta-hydroxy-kauran-17-yl ent-16beta3-kauran-17-oate (1); ent-16alpha-hydroxy-kauran-17-yl ent-16beta-kauran-17-oate (2) by means of spectral analysis and chemical evidence.

Dimerization↗
PubMed1999

Chemical constituents of Isodon melissoides.

Four new diterpenoids, melissoidesin E (1), F (2), G (4) and H (5), together with one known diterpenoid and two lignan glycosides, were isolated from aerial parts of Isodon melissoides. Their structures were established by spectral analysis and comparison with related compounds. The lignan glycosides (compounds 7 and 8) were the first examples to be isolated from the genus Isodon plants.

Diterpenes↗