Biomedical subjects
Publications and source records attributed to C Chen.
It has been reported that curdione is a major component in Chinese traditional herb ezhu. But no curdione was found in the herb ezhu collected from Guangdong province, instead a furan sesquiterpene was isolated. Its structure and configuration were determined by the analysis of IR, UV, MS, NMR and circular dichroism.
Putting the alcohol-extract from scorpion in the ordinary aqueous solution of 15% pork bile and having it cultured at the temperature of 37 degrees C have proved for the first time that in contrast with the chemical albendazole, Scorpion has a conspicuous effect on the external killing of the cysticercus cellulosae, The action of killing cysticercus cellulosae has almost nothing to do with the difference of processed products or of the parts used in medicine.
A technique of vaginal reconstruction using bilateral, perineal-thigh flaps with subcutaneous pedicle is described. In this procedure, the flaps were raised bilaterally and introduced into an artificial space between the urinary bladder and rectum. The blood supply for the flaps flows from the perineal artery through anastomotic branches to the external pudendal artery. The authors used the technique on four patients, and all the flaps survived entirely. There was no complication. According to a more than two-year follow-up survey, the reconstructed vaginas are expansible and contract little. No stent is needed. There is good sensitivity in the wall of the artificial vagina because sensory nerves run through the flaps.
The laryngeal mask airway (LMA), a new type of airway, when it is inserted blindly into the hypopharynx forms a seal around the larynx and allows easy and convenient spontaneous or controlled positive pressure ventilation. A clinical application of the LMA to 70 surgical patients in our hospital have been evaluated. LMA was successfully applied to 68 (97%) patients who all received general anesthesia with unobstructed controlled ventilation. The patency of the airway did not change throughout the course of anesthesia. There were 2 patients whose airway was obstructed at the first attempt due to downfolding of epiglottis; in one of them the obstruction was confirmed by flexible fibreoptic laryngoscopy. Subsequent placement was successful in these 2 patients. Insertion failure was seen in 2 patients respectively due to small mouth and excessive salivation. The placement of LMA does not require laryngoscopy and there is no fear of misplacement in the esophagus. It becomes obvious that the LMA would substantially gain a place in the armamentarium in anesthesia and we think that its use would be of interest to anesthesiologists.
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The study has shown that the extracts from leaves of Ginkgo biloba can significantly improve the NaNO2 and scopolamine induced impaired memory in mice. The potency of the ethanolic extract is greater than that of the aqueous extract. The ethanolic extract acts favorably on the memory function of normal animals. Both extracts help to prolong the survival time of mice receiving 200 mg/kg(ip)NaNO2.
2-Chloro-6-methoxy-8-nitroquinoline was reacted with substituted benzyl alcohols (or sodium methanol) and then brominated to give 2-substituted benzyloxy-6-methoxy- and 2,6-dimethoxy-5-bromo-8-nitroquinolines (compounds 5-8 in Table 1). These products were condensed with substituted phenols to form corresponding 5-substituted phenoxy compounds (9-19 in Tables 1 and 2) which were subsequently reduced to afford 2-substituted benzyloxy-6-methoxy- and 2,6-dimethoxy-5-substituted phenoxy-8-aminoquinolines (20-28, 47 and 48 in Tables 3 and 6). Condensation with 4-bromophthalimidopentane yielded corresponding 8-(4-phthalimido-1-methylbutyl)aminoquinolines (29-37, 49 and 50 in Tables 4 and 6) which were subsequently treated with hydrazine hydrate to give 2-substituted benzyloxy-6-methoxy- and 2,6-dimethoxy-5-substituted phenoxy-8-(4-amino-1-methylbutyl)amino-quinolines, compounds III and IV (38-46, 51 and 52 in Tables 5 and 6), the analogues of primaquine. Compounds III and IV were tested against Plasmodium yoenii in mice infected with sporozoites. The parasitaemia of 80% and 90% of tested mice was negative at an oral single dose of 100 mg/kg of compounds 39 and 45, respectively. The results of further studies on compound 45 showed that the parasitaemia of 80% of mice was negative at a single dose of 20 mg/kg, and the acute toxicity in mice was less than that of primaquine.
The hypothesis that endogenous chemical nitrosation in the normal stomach in early life could play a crucial role in inducing chronic atrophic gastritis/intestinal metaplasia in later life was tested by applying the N-nitrosoproline (NPRO) test to 12-h urine samples from about 50 children (aged 8-14 years) living in high- and low-risk areas for stomach cancer. The median values of NPRO and the sum of four nitrosamino acids analysed were 0.28-0.84 micrograms/12 h and 0.75-1.75 micrograms/12 h, respectively. The NPRO level after proline intake was significantly higher in children from a high-risk area than in those from a low-risk area (p less than 0.04), and markedly reduced after ingestion of ascorbic acid and proline (p less than 0.05). Urinary nitrate level was lower than that of adults. NPRO levels on the day of proline intake, however, correlated well with nitrate levels (p less than 0.001), indicating that children in a high-risk area in Costa Rica have high endogenous nitrosation potential. Blood samples were also collected from about 300 children (aged 7-20 years) and analysed for antibodies against Campylobacter pylori, a suspected gastritis-causing bacteria. About 71% of children in both high- and low-risk areas for stomach cancer had antibodies. In addition, raw and cooked beans, which are consumed very frequently in Costa Rica, were collected from families in both areas and analysed for levels of nitrite/nitrate, total N-nitroso compounds and genotoxicity in the SOS chromotest.(ABSTRACT TRUNCATED AT 250 WORDS)
We are investigating the interrelationships between levels of total N-nitroso compounds (NOC), genotoxic activity (both before and after nitrosation), degree of bacterial colonization in gastric juice and degree of severity or absence of precancerous lesions of the stomach. The mean level of constitutive total NOC in gastric juice was similar in the different groups of patients, but it was higher in acidic gastric juice (n = 30) than in gastric juice at pH greater than 4.5 (n = 12). Acid-catalysed nitrosation of gastric juice in vitro increased the concentration of total NOC by up to several thousand fold, to a maximum of 1330 mumol/l. Genotoxicity, expressed as SOS-inducing potency per 100 microliters of gastric juice was measurable in only 20% of gastric juice samples tested. After acid-catalysed nitrosation, however, all samples showed genotoxic activity, the mean SOS-inducing potency being four to seven times greater than the corresponding constitutive value. There was no association between the mean SOS-inducing potency of gastric juice and the severity of precancerous lesions. The mean SOS-inducing potency of neutral or basic gastric juice was slightly greater than that of acidic samples. In a kinetic study on N-nitrosation of gastric juice in vitro, a mixture of amino and amido substrates was nitrosated; both qualitative and quantitative individual differences in nitrosatable substrates in gastric juice were seen. Fractionation of acidic, neutral and basic nitrosated gastric juice samples revealed a preponderance of nonvolatile, unknown NOC with varying polarities. The results of our study suggest that only pH determines the nature and level of precursors of NOC and of nitrosation-dependent genotoxins in gastric juice.
This paper deals with the Bencaological records of the traditional Chinese drug Tianmingjing and the reason for its different names in use today. The traditional Chinese drug Heshi should be the fruit of Artemisia cina, rather than that of Carpesium abrotanoides. The present application of Tianmingjing in China is also discussed.
We have studied the cytotoxicity of Mistletoe lectin-1 (ML-1), a cytotoxic protein produced by Viscum album, in CHO and V79 cells and in mutant cell lines altered in Golgi functions or in endosomal acidification. In wild-type CHO cells, cytotoxicity of ML-1 was greatly enhanced by ammonium chloride or nigericin. A CHO mutant defective in endosomal acidification (DMPR-2), which is resistant to diphtheria toxin, modeccin and Pseudomonas aeruginosa exotoxin A and hypersensitive to ricin, showed increased sensitivity to ML-1. MonR-31 and MF-1 are monensin- and compactin-resistant mutants derived from CHO and V79 cell lines, respectively, and are presumably altered in Golgi functions. The cytotoxicity of ML-1 was found to be increased in both MonR-31 and MF-1 cells as compared with their parental cells. These results indicate that the effects of chemicals or mutations altering endosomal acidification and Golgi functions on the cytotoxicity of ML-1 are similar to those on ricin cytotoxicity. Our results suggest that the cytotoxicity of ML-1 is enhanced by an increase in endosomal pH, as well as by chemicals or mutations altering the structure/functions of the Golgi regions. Like ricin, the intoxication process of ML-1 may involve the Golgi regions.
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The patient we have described had lower extremity numbness, paresthesias, constipation, urinary retention, and sexual dysfunction. Laboratory evaluation confirmed a diagnosis of acute intermittent porphyria (AIP). Vitamin B6 and glucose therapy initiated resolution of symptoms. The sensory neuropathy described here is unusual, and we believe sexual dysfunction is a previously unreported manifestation of AIP.
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Two lactotroph subpopulations differing in their functional properties have previously been isolated from lactating female rats. It was found that adult female rats at proestrus similarly yield two subpopulations of lactotrophs, whereas those from adult female rats at metestrus show different properties and in males only one functional population is found. As the period of lactation and proestrus are characterised by high circulating estrogen levels, estrogen is considered to modify lactotroph properties in the female, and as the functional differences concern the lactotroph responsiveness to TRH, it is supposed that lactotroph heterogeneity provides a means for particular secretory patterns during lactation and at proestrus.
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