Biomedical subjects

D S Liang

Publications and source records attributed to D S Liang.

18 recordsLinked to original sources

PubMed1999

Determination of ferulic acid in Angelica sinensis and Chuanxiong by capillary zone electrophoresis.

Ferulic acid in extracts of raw herbs was separated by capillary zone electrophoresis in the buffer solution of 10 mmol/L Na(2)B(4)O(7). The simple and rapid method was linear, ranging from 5 to 100 microg/mL, and had a good reproducibility with the RSD below 2%. The contents of ferulic acid in Angelica sinensis and Chuanxiong could be easily determined within 15 min with no pretreatment and no interference.

Coumaric Acids↗

PubMed1999

Determination of berberine in Rhizoma coptidis and its preparations by non-aqueous capillary electrophoresis.

A non-aqueous capillary electrophoretic method was established for the determination of berberine in Rhizoma coptidis and its preparations. The effects of organic solvent and the concentrations of sodium acetate were studied, which showed that berberine in extracts of traditional Chinese medicine can be separated successfully in a buffer solution of 75 mmol/L of sodium acetate in methanol containing 1 mol/L of acetic acid. The simple and rapid method was linear in the range 25-200 microgram/mL of berberine and had a good reproducibility, with the relative standard deviation below 2%. Non-aqueous capillary electrophoresis is a satisfactory system for the analysis of alkaloids in traditional Chinese medicine.

Anti-Infective Agents, Local↗

PubMed1999

Determination of tetrahydropalmatine in Chinese traditional medicine by nonaqueous capillary electrophoresis.

Tetrahydropalmatine in Rhizoma corydalis and its preparations were separated and determined with no pretreatment in the buffer solution of 50 mmol/L of sodium acetate in methanol containing 2 mol/L acetic acid.

Berberine Alkaloids↗

PubMed1991

[Stroke and thyroid hormones].

The levels of thyroid hormones were determined by RIA in 65 cases in with stroke, in which 42 cases showed low T3 levels (64.6%). The rates of abnormal T3 and rT3 were much higher in hemorrhage group (72.5%) than those in infarction group (52%). T3 and rT3 abnormalities were apparent in the acute stage compared to those in the chronic stage (P less than 0.01), and closely correlated with size of lesions, that is, size of lesions had negative correlation with T3 and T3/rT3 but positive correlation with rT3 when the volume of hemorrhage was more than 30 ml or the area of infarction more than 20 cm2. Determination of T3 and rT3 levels in patients with stroke may be helpful in assessing the severity and prognosing.

Adolescent↗

PubMed1990

[Induction of retarded exoerythrocytic schizonts by chloroguanide resulting in delayed parasitaemia of Plasmodium inui in Macaca mulatta].

Three Rhesus monkeys inoculated with a large number of sporozoites of Plasmodium inui dissected from the salivary glands of infected mosquitoes, Anopheles dirus. Two of the monkeys (inoculated with 8.06 x 10(5) and 1.3 x 10(7) sporozoites, respectively) were treated with chloroguanide base 6 mg/(kg.d) x 4 d starting from 24 h after the inoculations and the other one (inoculated with 5.93 x 10(6) sporozoites) was not treated with chloroguanide as control. The primary parasitaemia attacks occurred in the former 2 monkeys were 31 and 25 d respectively after inoculation, while in the control was 7.5 d. Liver biopsies were done in all of the 3 monkeys, normal schizonts were seen in the control monkey on d 8 after inoculation, while none were detected in the 2 monkeys treated with chloroguanide. However, the retarded exoerythrocytic schizonts were found by indirect fluorescent antibody test (IFAT) in liver sections of the monkey inoculated with 1.3 x 10(7) sporozoites. Therefore, it is evident that moderate doses of chloroguanide retarded the formation of schizonts and thus delayed the primary parasitaemia.

Animals↗

PubMed1988

Observations on early and late post-sporozoite tissue stages in primate malaria. V. The effect of pyrimethamine and proguanil upon tissue hypnozoites and schizonts of Plasmodium cynomolgi bastianellii.

Two rhesus monkeys were each infected with 2.1 x 10(6) sporozoites of Plasmodium cynomolgi bastianellii; one was treated with 1.0 mg of pyrimethamine base per kg body weight for 5 d after sporozoite inoculation. A further 2 monkeys were each infected with 9.75 x 10(6) sporozoites of the same parasite; one was treated with 10 mg of proguanil per kg body weight for 4 out of 5 d after inoculation. The treated monkeys showed a delayed primary parasitaemia and relapses. In sections of liver biopsies taken 7.5 d after sporozoite inoculation, all monkeys showed numerous hypnozoites. However, there were no full grown schizonts and only rare retarded schizonts in the treated monkeys, in contrast to the untreated monkeys which had many mature or nearly mature schizonts. Later biopsies confirmed the continued presence of hypnozoites in all monkeys.

Animals↗

PubMed1985

Qinghaosu-induced changes in the morphology of Plasmodium inui.

The ultrastructural changes induced by the administration of the antimalarial drug, qinghaosu, were studied in monkeys (Macaca assamensis) infected with Plasmodium inui. Significant changes, notably mitochondrial swelling within the parasites but not within host cells, were first observed 2.5 hr after exposure to qinghaosu. This suggests that the target of qinghaosu may be the parasite's mitochondria, as occurs with primaquine. This is in contrast to the most widely used antimalarial drug, chloroquine.

Animals↗

PubMed1982