Preventive effect of artemether in rabbits infected with Schistosoma japonicum cercariae.

AIM: To study the effect of artemether (Art) for prevention of schistosomal infection. METHODS: Rabbits with single infection or reinfection with Schistosoma japonicum cercariae were treated intramuscularly (i.m.) or intragastrically (i.g.) with Art 5 -20 mg.kg-1 on d 7-15 after the first infection, followed by various regimens. RESULTS: When rabbits were injected i.m. Art 7.5 mg.kg-1 (i.e., one half of the effective dose given i.g. on d 7) followed by once every week for twice, the female worm reduction rate was only 42%. In infected rabbits treated i.g. with Art 10-20 mg.kg-1 given in the same administration schedule, the female worm reduction rates were > 91%. When Art 15 mg.kg-1 was given to rabbits on d 7-14 and the following dose of the drug was given at intervals of 7-14 d, the female worm reduction rates were > 94%. In rabbits reinfected with cercariae, the female reduction rate of Art given i.g. once a week for 3 times since d 8 after the first infection was 96% which was similar to that given once a week twice since d 14 after the first infection. CONCLUSION: Art should be given i.g. on d 7-15 after infection, followed by repeated dosing once every 7-15 d for a total of 3 doses. Art given i.g. daily for 2 consecutive days or given at 1-wk intervals since 7-15 d after infection also showed preventive effect.

[2 Hz and 100 Hz electroacupuncture accelerate the expression of genes encoding three opioid peptides in the rat brain].

Previous findings from this laboratory have shown that low (2 Hz) and high (100 Hz)-frequency electroacupuncture (EA) accelerated the release of different kinds of opioid peptides in the CNS. In the present study, we tried to elucidate whether EA of different frequencies would affect the transcription of genes encoding different opioid peptides. Digoxin-labeled antisense cRNA probes were used for in situ hybridization to detect the mRNA encoding preproenkephalin (PPE), preprodynorphin (PPD) and proopiomelanocortin (POMC) in the rat brain. The results showed that: (1) Neither 2 Hz nor 100 Hz EA altered the POMC mRNA level in the rat brain. (2) EA of the two frequencies induced a similar degree of increase of PPE mRNA in rostromedial reticular formation (gigantocellular, paragigantocellular and lateral reticular nucleus); whereas in supraoptic nucleus, suprachiasmatic nucleus, arcuate nucleus, paraventricular hypothalamic nucleus, ventromedial nucleus and the nucleus of lateral lemniscus, 2 Hz EA induced a higher PPE mRNA expression than 100 Hz EA. (3) 100 Hz EA markedly increased the PPD mRNA levels in supraoptic nucleus, paraventricular hypothalamic nucleus, ventromedial nucleus and parabrachial nucleus, while 2 Hz was without effect. Since de novo peptide synthesis is regarded as a natural outcome following accelerated peptide release, the present results substantiate our previous observation that EA of different frequencies exert different acceleratory effects on the release and synthesis of different opioid peptides in the central nervous system.

Brain substrates activated by electroacupuncture of different frequencies (I): Comparative study on the expression of oncogene c-fos and genes coding for three opioid peptides.

Low and high frequency electroacupuncture (EA)-produced analgesia have been shown to be mediated by different brain substrates and different opioid peptides. In this study, Fos-like immunoreactivity (FLI) and in situ hybridization of the three opioid mRNAs were used to examine the effect of low (2 Hz) and high (100 Hz) frequency EA on neuronal activities, and the expression of opioid genes. 2 Hz and 100 Hz EA induced a markedly different spatial patterns of Fos expression in the rat brain, suggesting there are distinct neuronal pathways underlying EA of different frequencies. Likewise, 2 Hz and 100 Hz EA exert differential effects on opioid gene expression: while 2 Hz EA induced a more extensive and intensive preproenkephalin (PPE) mRNA expression than 100 Hz EA, it had no effect on preprodynorphin (PPD) mRNA expression which was significantly increased by 100 Hz EA stimulation. In contrast, EA of both frequencies did not affect POMC mRNA expression.

Brain substrates activated by electroacupuncture (EA) of different frequencies (II): Role of Fos/Jun proteins in EA-induced transcription of preproenkephalin and preprodynorphin genes.

Antisense oligodeoxynucleotides (ODNs) of c-fos and/or c-jun were used in this study to investigate the role of Fos and Jun proteins in electroacupuncture (EA)-induced transcription of the opioid genes, preproenkephalin (PPE), preprodynorphin (PPD) and proopiomelanocortin (POMC). As the results showed, EA-induced Fos and fun expression was blocked efficiently and specifically by e-fos and c-jun antisense ODNs, respectively. This treatment significantly prevented EA-induced PPD, but not PPE, mRNA expression. These results suggest that Fos and Jun proteins are involved in PPD rather than PPE gene transcription activated by EA stimulation.

C-Fos proteins are not involved in the activation of preproenkephalin gene expression in rat brain by peripheral electric stimulation (electroacupuncture).

The present work was designed to study the role of the oncogene product c-Fos in activating the transcription of preproenkephalin (PPE) gene following a kind of peripheral electric stimulation known as electroacupuncture (EA) stimulation. The temporal patterns of rat brain c-fos and PPE mRNA expression were evaluated using the method of Northern blotting, showing that c-fos mRNA expression, which peaked at 2 h after the termination of EA, was always ahead of the PPE mRNA expression which began at 4 h and peaked at 48 h after EA. The methods of immunocytochemistry (ICC) and in situ hybridization (ISH) techniques were combined to identify the co-existence of c-Fos protein and PPE mRNA at the cellular level. The results showed that only a small percentage of PPE mRNA-containing neurons depicts Fos-like immunoreactive nuclei. These findings suggest that c-Fos protein may not be involved in the activation of brain PPE gene transcription induced by peripheral electric stimulation.

[Comparative study on the expression and interaction of oncogene c-fos/c-jun and three opioid genes induced by low and high frequency electroacupuncture].

The present work was designed (a) to study comparatively the effect of 2Hz and 100Hz electroacupuncture (EA) on the expression of oncogene c-fos/c-jun and three opioid (preproenkephalin-PPE; preprodynorphin-PPD; proopiomelanocortin-POMC) genes in the rat brain; (b) to clarify the role of Fos/Jun (AP-1) on opioid genes expression induced by EA stimulation through specific blockade of EA-induced Fos/Jun expression using antisense oligodeoxynucleotides (ODNs) of c-fos/c-jun. The results were: (a) 2Hz and 100Hz EA induced differential Fos expression in different brain areas; (b) EA of both frequencies accelerated PPE gene transcription, but 2Hz EA was more effective than 100Hz EA; (c) PPD expression was accelerated by 100Hz EA, but not by 2Hz EA; (d) the blockade of Fos/Jun expression by c-fos/c-jun antisense ODNs prevented EA from accelerating PPD but not PPE mRNA expression.

[Clinical observation on diabetic nephropathy treated with alcohol of Abelmoschus manihot].

Sixty-eight cases of non-insulin dependent diabetes mellitus (NIDDM) complicated with nephropathy were randomly divided into two groups: treated group, 35 cases treated with alcohol extraction of Abelmoschus manihot, Gliclazide and Captopril tablets; control group, 33 cases treated with Gliclazide and Captopril tablets, over a period of 8 weeks. The total effective rate in treated and control group were 83.87% and 31.03%(P < 0.01), urinary micro-albumin were 31.7 mg/L and 76.3 mg/L (P < 0.05), proteinuria were 0.41 g/24h and 0.77 g/24h (P < 0.01), blood beta 2-microglobulin were 3317.8 ng/ml and 3473.1 ng/ml (P < 0.05), urinary beta 2-microglobulin were 367.2 ng/ml and 641.5 ng/ml (P < 0.01), urinary N-acetyl-beta-glucosaminidase (NAG) were 26.3 u/L and 66.7 u/L (P < 0.01), plasma lipid peroxide (LPO) were 6.13 nmol/L and 8.78 nmol/L (P < 0.05), and plasma superoxide anion were 8.36 kcpm and 10.42 kcpm respectively (P < 0.05). It was suggested that Abemoschus manihot alcohol extraction could eliminate oxygen free radicals, alleviate renal tubular-interstitial diseases, improve renal function and reduce proteinuria.

[Screening antihydatid drugs using cultivated germinal cells of Echinococcus granulosus].

Germinal cells isolated from Echinococcus granulosus cysts harbored in mice have been maintained in an in vitro culture system containing RPMI 1640 supplemented by 20% calf serum, and used as a model for screening anti-hydatid drugs. When the germinal cells were maintained in the medium for 6 days, the cell proliferation rate was rather high in the first four days but declined in the last two days. In screening drugs, 1.4 x 10(6) germinal cells were exposed to known effective drugs against metacestodes of E. granulosus in mice, such as mebendazole (Meb), albendazole (Alb) or praziquantel (Pra) at various concentrations. One to three days after exposure, cell counts were made daily in 3 samples of each drug concentration. The mean cell number of each group was compared with that of the control and the inhibition rate of the cell was then calculated. The results showed that the minimal effective concentrations of Meb, Alb and Pra, were 1.0 (48 h), 2.5 (24 h) and 10.0 (72 h) micrograms/ml, respectively, while the inhibition rates of the cell were 34.1, 55.7 and 18.5%. Interestingly, the in vitro effects of Meb, Alb and Pra were consistent to those obtained from the in vivo tests, ie Meb > Alb > Pra. Nevertheless, after exposure of germinal cells to Meb at 2.5 micrograms/ml for 24 h, the cells appeared in roughness, indistinction, shrunk or swelling, collapse, deformation and hole-like feature detected by light microscopy and scanning electron-microscopy, while the ultrastructure alterations of the cells noted by transmission electron-microscopy were lysis in cytoplasm, disruption or disappearance of nucleus and even darkness of the whole cell.(ABSTRACT TRUNCATED AT 250 WORDS)