Effects of zinc-methionine on growth performance, intestinal flora and immune function in pigeon squabs.

1. Different concentrations of zinc-methionine (Zn-Met) were given to pigeon squabs, and the resulting effects on growth, immune functions and intestinal microflora were investigated from hatching to 28 d of age. A total of 180 artificially hatched pigeon squabs were randomly allotted to each of three treatments with three replicates of 20 squabs. The three treatments given were either one ml (2 mg/ml) Zn-Met, one ml (10 mg/ml) Zn-Met or one ml 0.9% NaCl solution. 2. The results showed that Zn-Met improved the growth performance of squabs. The average daily and average weekly weight gain was significantly greater in squabs treated with Zn-Met than in the control group. 3. The group given 2 and 10 mg supplemental Zn-Met had heavier thymus, spleen and bursa of Fabricius than the control group at d 28. 4. Maternal antibody titres against Newcastle disease haemagglutination inhibition and alpha-naphthyl acetate esterase were significantly higher in squabs treated with supplemental 2 and 10 mg Zn-Met compared to the control group at d 14 and d 28. 5. Additionally, the squabs given supplemental 2 mg Zn-Met exhibited significantly higher Bacillaceae, Lactobacillus, Enterococcus and Bifidobacterium populations at d 14 and d 28, but lower Escherichia coli populations at d 28 compared to the control group. On the contrary, Lactobacillus, Enterococcus and Bifidobacterium populations were significantly decreased with 10 mg Zn-Met at d 28. 6. This study indicates that supplementation with Zn-Met has a positive effect on growth performance, immune function and regulation of intestinal flora in pigeons. An inclusion level of 2 mg seems to be better than 10 mg Zn-Met per day per bird.

[Experimental pharmacodynamic study on the anti-convulsion effect of shenpu decoction].

OBJECTIVE: To observe the anti-convulsion effect of Shenpu Decoction (SPD). METHODS: Experiments were conducted in three acute convulsion models (cardiazol seizure, strychnine convulsion and maximal electrical shock). Models were divided into the control group (A, treated by normal saline), the high, middle and low dose SPD groups (B, C and D, treated with SPD 9 g/kg, 6 g/kg and 4 g/kg respectively), and the nitrazepam treated group (E). The anti-convulsion effect of SPD was evaluated by 50% convulsion dose (CD50) detected in each group. RESULTS: In cardiazol convulsion model, the CD50 detected in group A-E were 63.3 +/- 3.4 mg/kg, 116.2 +/- 3.4 mg/kg, 105.6 +/- 3.7 mg/kg, 74.0 +/- 3.7 mg/kg and 197.2 +/- 3.3 mg/kg respectively, while they were 0.71 +/- 0.04 mg/kg, 1.21 +/- 0.04 mg/kg, 1.19 +/- 0.04 mg/kg, 0.94 +/- 0.04 mg/kg and 1.16 +/- 0.04 mg/kg respectively in the strychnine convulsion model, and 67.1 +/- 2.6 V, > 140 V, 109.4 +/- 3.5 V, 84.4 +/- 3.1 V and 128.4 +/- 3.9 V in the maximal electrical shock model respectively. CONCLUSION: SPD has a good anticonvulsion effect.

Functional expression of Shaker K+ channels in cultured Drosophila "giant" neurons derived from Sh cDNA transformants: distinct properties, distribution, and turnover.

Expression of transgenic Shaker (Sh) channels has not previously been examined in Drosophila neurons. We studied K+ current by whole-cell recording in cultured "giant" neurons derived from germline transformants. Independent lines were generated by using a P-element vector, in which transcription of the 29-4 cDNA, one of the Sh splicing variants (Iverson and Rudy, 1990), was under the control of a heat shock (HS)-inducible promoter. Transformants in wild-type and two different Sh mutant backgrounds all exhibited an HS-inducible, A-type K+ current that was characterized by a much slower recovery from inactivation and a higher sensitivity to 4-aminopyridine than native K+ currents of Sh 29-4 currents expressed in Xenopus oocytes. Despite similarities in the kinetic and pharmacological properties of the HS-induced current in all backgrounds examined, host-dependent differences in the peak current amplitude have been consistently observed between multiple lines of 29-4 ShM and 29-4 Sh120 that might reflect differential channel subunit assembly in different hosts. Isolation of the novel 29-4 currents allowed determination of the channel turnover rate in cultured neurons. These currents persisted for up to 3 d or more, comparable with the durations previously reported for Na+ and Ca2+ channels. Surprisingly, the percentage of cells expressing inactivating K+ currents remained approximately the same with or without HS induction, suggesting that some mechanisms exist to restrict functional expression of inactivating K+ channels, including transgenic Sh channels and those not encoded by the Sh locus, to certain types of neurons.

[Growth capability of epithelial cell line of human poorly differentiated nasopharyngeal carcinoma and its response to Chinese medicinal herbs and marine drugs].

By 3H-TdR incorporation, dye exclusion and cell colony-forming tests, the capability of short-term in vitro growth of the epithelial cell line of human poorly differentiated nasopharyngeal carcinoma (CNE-2Z) was assayed. At the same time, its response to 54 kinds of Chinese medicinal herbs and marine drugs was studied. The results showed that the 3H-TdR incorporation rate of cells was 1.8 +/- 0.02%, reproduction rate was 60.9 +/- 13.0% and colony-forming rate, 40.8 +/- 3.5%. As to the ratios of the three cell growth indexes and response to medicines, the Chinese medicinal herbs and marine drugs causing the reduction of colony-forming and cell survival ratios were predominant (64.8% and 40.7%). The results indicate that the majority of drugs possess the cytotoxic and inhibitory effect on cell reproduction to different degrees. The composite cell response to every kind of drug could be divided into 6 types: descending, ascending, peaked, valley-like, depressed and stable. The depressing type drugs might inhibit or arrest the cell growth of nasopharyngeal carcinoma and are worthy of further study.

Wikstroemia indica promotes development of nasopharyngeal carcinoma in rats initiated by dinitrosopiperazine.

Nasopharyngeal carcinoma was induced in an initiation/promotion model in rats by s.c. injection of dinitrosopiperazine in the nasopharyngeal cavity. This was followed by repeated 10-cal administration of an extract of roots of the Chinese medicinal herb WI (botanical family: Thymelaeaceae). Three groups of rats were used: group-1 received DNP followed by repeated WI; group-2 received DNP once; group-3 received WI repeatedly. At 180-205 days after DNP + WI administration 26% of the rats in that group exhibited NPC (two were carcinomas in situ and four were early infiltrating carcinomas). In the other two groups no carcinomas were found. In the group which received DNP followed by WI, other pathological changes, such as hyperplasia of nasopharyngeal epithelium, squamous metaplasia, and papillary hyperplasia, were also more frequent than that in the other two groups.