Effects of Crude Toxins from Colletotrichum gloeosporioides on Growth of Dendrobium officinale Kimura et Migo / 广州中医药大学学报

To explore the effects of crude toxins from Colletotrichum gloeosporioides(C. gloeosporioides)on the growth of Dendrobium officinale Kimura et Migo(D. officinale),and to provide early basis for thescreening and cultivation of the resistant variants of C. gloeosporioides. Methods Seedlings of D. officinal werecultivated in MS medium added with different concentrations of the crude toxins from C. gloeosporioides. Theeffects of the crude toxin on the growth of seedlings were observed, and the optimum resistance -selectionthreshold was preliminarily screened. Results In the concentration range of 5％ - 15％(volume fraction),crudetoxins from C. gloeosporioides increased the plant height,stem diameter,number of new bud,root number,and fresh mass of D. officinale,among which the effect of 5％(volume fraction)of crude toxins was the moststrongest. In the concentration range of 35％ - 40％(volume fraction),crude toxins suppressed the plant height,leaf number,number of new bud,root number,and the fresh mass of D. officinale. When cultured with 20％(volume fraction)crude toxins, D. officinale was blooming, and the flowers appeared variation phenomenon.Conclusion The crude toxins from C. gloeosporioides have biological activity and certain toxicity,which can beconsidered as a selection agent instead of pathogenin in vitro to screen the resistant variant of D. officinale,butthe optimum resistance-selection threshold still needs further research.

[Investigation and analysis of neonate deformity in water arsenic exposure areas].

OBJECTIVE: To explore the level and feature of neonate deformity in water arsenic exposure areas, as to finding out an evidence for the study and prevention of the arsenic exposure. METHODS: The birth situation of neonate was surveyed from 1998 to 2004 in water arsenic exposure areas according to cross-sectional survey. The results were classified in accordance with ICD-10 and common surveillance of china. The population of Shanyin County served as the common people and the data were analyzed by SPSS 11.5 for windows. RESULTS: The neonates surveyed were 2467 cases. There were 49 neonates deformity found in this investigation, giving a neonate deformity rate of 198.62 per 10,000 cases, which was shown significantly higher in water arsenic exposure areas than in the normal (U = 3.23, P < 0.01), with types of nervous system deformity, limbs deformity and congenital heart disease as in system classification. There was no significant difference of deformity rate in different sex neonates (chi2 = 0.32, P > 0.05). CONCLUSION: The drinking high-arsenic water over a long period of time should be a risk factor of neonate deformity. Prevention and treatment of endemic arsenic exposure should be urgently needed.

Arsenic and fluoride exposure in drinking water: children's IQ and growth in Shanyin county, Shanxi province, China.

BACKGROUND: Recently, in a cross-sectional study of 201 children in Araihazar, Bangladesh, exposure to arsenic (As) in drinking water has been shown to lower the scores on tests that measure children's intellectual function before and after adjustment for sociodemographic features. OBJECTIVES: We investigated the effects of As and fluoride exposure on children's intelligence and growth. METHODS: We report the results of a study of 720 children between 8 and 12 years of age in rural villages in Shanyin county, Shanxi province, China. The children were exposed to As at concentrations of 142 +/- 106 microg/L (medium-As group) and 190 +/- 183 microg/L (high-As group) in drinking water compared with the control group that was exposed to low concentrations of As (2 +/- 3 microg/L) and low concentrations of fluoride (0.5 +/- 0.2 mg/L). A study group of children exposed to high concentrations of fluoride (8.3 +/- 1.9 mg/L) but low concentrations of As (3 +/- 3 microg/L) was also included because of the common occurrence of elevated concentrations of fluoride in groundwater in our study area. A standardized IQ (intelligence quotient) test was modified for children in rural China and was based on the classic Raven's test used to determine the effects of these exposures on children's intelligence. A standardized measurement procedure for weight, height, chest circumference, and lung capacity was used to determine the effects of these exposures on children's growth. RESULTS: The mean IQ scores decreased from 105 +/- 15 for the control group, to 101 +/- 16 for the medium-As group (p < 0.05), and to 95 +/- 17 for the high-As group (p < 0.01). The mean IQ score for the high-fluoride group was 101 +/- 16 and significantly different from that of the control group (p < 0.05). Children in the control group were taller than those in the high-fluoride group (p < 0.05); weighed more than the those in the high-As group (p < 0.05); and had higher lung capacity than those in the medium-As group (p < 0.05). CONCLUSIONS: Children's intelligence and growth can be affected by high concentrations of As or fluoride. The IQ scores of the children in the high-As group were the lowest among the four groups we investigated. It is more significant that high concentrations of As affect children's intelligence. It indicates that arsenic exposure can affect children's intelligence and growth.