Showing papers by "Tzi Bun Ng published in 1995"
TL;DR: A polysaccharide-peptide complex (PSPC) with immunomodulatory and antitumor activities was obtained from a submerged mycelial culture of Tricholoma sp.
102 citations
TL;DR: Nine sterols and triterpenes isolated from Codonopsis pilosula and Adenophora stricta were used as reference compounds and indicated that the four genera could be distinguished from one another.
29 citations
TL;DR: Ulastructural analysis of the visceral yolk sac revealed abnormalities including decrease in the amount of microvilli, reduction in the number of storage vesicles, appearance of large vacant vacuoles and decrease inThe number of pinocytotic invaginations on the apical surface of the yolksac epithelium.
15 citations
TL;DR: The findings show than melatonin, methoxytryptamine and methxytryptophol produced an embryotoxic effect on embryos at the early somite stage in vitro while only methoxyllryptamine had an adverse effect on embryonic development in vivo.
Abstract: 1.
1. A subcutaneous injection of hydroxyindoleacetic acid (HIAA), melatonin (MEL), methoxytryptophol (MTP) or methoxytryptamine (MTA) (1 mg/25 g body wt/injection) at 8.5 days post-coitum (p.c.) did not produce any effect on the development of embryos in utero at 10.5 days p.c.
2.
2. Two subcutaneous injections (3 mg/25 g body wt/injection) of MTP, but not HIAA, MEL nor MTP, at 7.5 and 8.5 days p.c. brought about a decrease in gravid uterine weight and number of live fetuses and an increased incidence of early resorptions at 17.5 days p.c.
3.
3. MEL at doses 100 and 200 μg/ml, MTP at doses 50 and 100 μg/ml and MTA at 25, 50 and 100 μg/ml brought about an increase in the number of abnormal embryos cultured in vitro and an increased incidence of abnormal yolk sac circulation, body axis, optic and otic placodes, branchial apparatus, forelimb buds and cranial neural tube.
4.
4. The findings show that melatonin, methoxytryptamine and methoxytryptophol produced an embryotoxic effect on embryos at the early somite stage in vitro while only methoxytryptamine had an adverse effect on embryonic development in vivo.
13 citations
TL;DR: This review covers studies on herbal properties, resources, identification, physicochemical evaluation, cultivation, breeding, tissue culture, collection, processing, preparation, active principles and pharmacological activities of traditional and herbal Chinese drugs.
Abstract: 1. Progress made in pharmacognostic research by Chinese investigators in the last decade is summarized herein. 2. This review covers studies on herbal properties, resources, identification, physicochemical evaluation, cultivation, breeding, tissue culture, collection, processing, preparation, active principles and pharmacological activities of traditional and herbal Chinese drugs. 3. As a result of these research activities errors in species identification were spotted, new drug resources were revealed, new taxa were discovered, crude drugs were analyzed qualitatively and quantitatively, optimal conditions for cultivation and breeding of plants and animals used as drugs were formulated, the quality of some drugs was controlled, the drug processing procedures and storage conditions were evaluated, and the chemistry and pharmacology of a number of crude drugs were elucidated.
11 citations
TL;DR: The results revealed that when Glu 160 in trichosanthin was mutated to alanine or aspartate, the two aforementioned activities underwent a substantial decrease, however, the former mutein had a higher potency than the latter mutein, indicating the contribution from other amino acids in stabilizing the transition state complex of trichOSanthin.
Abstract: Trichosanthin, a ribosome inactivating protein, is known to possess embryotoxic and antiproliferative activities. In the present study recombinant trichosanthin and its muteins produced by site-directed mutagenesis were tested for these activities using whole embryo culture and cell culture. The results revealed that when Glu 160 in trichosanthin was mutated to alanine or aspartate, the two aforementioned activities underwent a substantial decrease. However, the former mutein had a higher potency than the latter mutein. When both Glu 160 and Glu 189 were mutated, the resultant mutant possessed very low antiproliferative and yet considerable embryotoxic activity, indicating the contribution from other amino acids in stabilizing the transition state complex of trichosanthin.
10 citations
TL;DR: It was found that the gonads and hearts of the drug-treated mice were histologically similar to those of control ani mals, and tissue damage was accom panied by elevations of liver LDH isozyme activity in the serum.
Abstract: Mature ICR mice were randomly divided into groups and treated with various doses (1 mg, 5 mg or 10 mg herb/25 g body weight) of a decoction of one of three following Chinese medicinal herbs: Aconitum carmichaeli, Aconitum kusnezoffi and Tripterygium wilfordii, once daily for 4 days. Twenty four hours after the last injection the animals were bled and the blood samples were stored at -20 degrees C until assay for liver lactate dehydrogenase (LDH) isozyme activity. The livers, kidneys, hearts and gonads were dissected out, immediately fixed in Bouin's fluid, and subsequently processed for histological examination. It was found that the gonads and hearts of the drug-treated mice were histologically similar to those of control animals. After treatment with the lowest dose of the herbs i.e. 1 mg/25 body weight, the liver and kidney did not undergo observable changes. However, the herbs at the doses of 5 mg and 10 mg/25 g body weight produced damaging effects on the liver and kidney, the effects produced by the higher dose being more dramatic. The tissue damage was accompanied by elevations of liver LDH isozyme activity in the serum.
6 citations