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Biological invasion refers to the process that organisms invade into another new environment through natural or man-made way from the original habitat, causing economic losses or ecological disasters to biodiversity, agriculture, forestry, animal husbandry and fishery production and human health. Human activities and the development of global integration accelerate the occurrence of biological invasion, which poses a serious threat to the global biodiversity and economy. Since entering the 21st century, biological invasion has continued. Pomacea canaliculata Lam, native to the Amazon River Basin of South America, was introduced into southern China as an aquatic economic animal in the 1980s because of its rich protein content and high nutrient content. Later, it was abandoned in the fields due to excessive blind breeding, too strong fishy smell and poor taste, and spread to the aquatic environment such as rice fields through canals and rivers. Because of its strong fecundity, adaptability and stress resistance, miscellaneous food habits and lack of natural enemies, the snail has become a disaster in many areas of southern China, which poses a major threat to the biodiversity, ecosystem, crops and aquatic plants in the invaded areas. In addition, Pomacea canaliculata is the intermediate host of Angiostrongylus cantonensis, which causes eosinophilic meningitis, and has indirect potential harm to human health. In 2000, the IUCN Expert Committee on alien invasive species listed Pomacea canaliculata as one of the world's 100 malignant alien invasive species. In March 2003, the State Environmental Protection Administration listed the first batch of 16 alien species to invade China. The control methods of Pomacea canaliculata can be divided into four aspects. First of all, physical methods are used to collect snails and eggs manually. During the peak breeding period, human resources are concentrated to collect snails in fields, canals and other areas. During the spawning period, bamboo chips and wooden sticks are inserted in the rice fields to attract the snails to lay eggs and destroy the collected eggs. However, this method has the characteristics of high frequency spawning, strong sustainability of prevention and control, rapid spread with the current, and it is difficult to control. In addition, the artificial fishing cost is high and the timeliness cannot be met for the large area where the Pomacea snail occurs. The second is chemical control. Though the molluscicides, such as spiromethane, tetraacetaldehyde and copper sulfate, are put in the rice fields, rice fields and channels at the same time. Although the effect is obvious, it is easy to cause serious environmental pollution if it is not used properly, and the snail is easy to produce drug resistance. The secondary biological method is to make use of the thin shell and meat of Fushou snail, which is high in protein, low in fat and has more in the areas where snails occur, ducks, fish and crabs are cultivated. However, in the process of biological control, it is necessary to strictly control the number of biological population to avoid animal feces polluting the water environment and damaging people's water sanitation. Finally, in order to prevent and control Pomacea canaliculata with camellia seed cake, saponins and other plant sources, it has become a hot spot in the field of snail control due to its long-term, economic and ecological safety to non target cells. However, there are few studies on the extraction and preparation of botanical toxicants and their toxic effects on Pomacea canaliculata. The results showed that castor seed was highly toxic, and the main toxic components were ricinine and ricin. Among them, ricin was one of the most toxic plant toxin proteins, which has a strong insecticidal and bactericidal effect. When it entered the animal body, it would be decomposed by the object itself, and it would not accumulate in the biological chain and produce drug resistance. Ricinine is a kind of alkaloid with low toxicity, which can cause vomiting and various toxic reactions. It can lead to liver and kidney damage, convulsion, hypotension and death. At present, there is no report on the toxicity of castor oil extract to Pomacea canaliculata. The biological soaking method was used to prepare the botanical toxicant from the extract of Ricinus communis L. seed. The toxic effects of different extract concentrations (0, 0.5, 1.5, 3.0, 4.5, 6.0 g/L) on the snails were studied. The liver tissue physiological and biochemical indexes of the snails treated with sublethal concentrations of 1.58 (LC25), 3.82 (LC50) and 6.05 (LC75) g/L and their correlation were further studied analysis of the mechanism of its toxic action. The results showed that after 48h treatment, the mortality of Pomacea canaliculata increased with the increase of time and concentration, and the mortality of Pomacea canaliculata was significantly different under different concentrations (P<0.05). The protein content (TP), malondialdehyde (MDA) content and catalase (CAT) activity in hepatopancreatic tissue were significantly different from those in the control group after 48h of sublethal concentration treatment. There was a significant negative correlation between catalase (CAT) activity and malondialdehyde (MDA) content (P<0.05). The extract of Ricinus communis L. seed can cause damage of liver tissue and disorder of metabolism by affecting the content of protein (TP), malondialdehyde (MDA) and the activity of catalase (CAT) in the liver tissue, so as to achieve the toxic effect. The results of molluscicidal test and physiological and biochemical indexes showed that castor seed had potential molluscicidal effect on Pomacea canaliculata. [ABSTRACT FROM AUTHOR]

Objective: To analyze the population genetics characteristics of mitochondrial DNA (mtDNA) in Gelao, Mulao, Maonan ethnic groups from Guizhou., Methods: Minisequenceing and restriction fragment length polymorphism (RFLP) were used to analyze 12 single nucleotide polymorphism (SNPs) of mitochondrial DNA in the 3 ethnic groups., Results: A total of 30 haplotypes were detected in 156 samples. The distribution of H1, H23 had differed between Mulao, Maonan and Gelao, respectively, and so did M7 among the three groups. The difference was statistically significant (P < 0.05). Mulao, Maonan had respectively differed from Gelao and the difference was also statistically significant (P < 0.05)., Conclusion: There was a great similarity in the distribution of haplotypes of the mtDNA among the three ethnic groups, except for some difference in the distribution of certain haplotypes.

Objective: To study the frequency of a 9 bp deletion polymorphism of mitochondrial DNA (mtDNA) in ethnic Miao, Buyi and Dong populations from Guizhou province., Methods: Polymerase chain reaction-polyacrylamide gel electrophoresis (PCR-PAGE) was used to detect the 9 bp deletion. The result was verified with DNA sequencing., Results: Two polymorphisms, including a standard pattern and a short pattern (the 9 bp deletion), were found among the three ethnic groups. The frequency of short pattern in 304 males was 23.0%. Respectively, those of Miao, Buyi and Dong ethnics were 28.6%, 26.8% and 13.7%. A statistically significant difference was detected among the three groups (P<0.05)., Conclusion: The frequencies of the 9 bp polymorphism were relatively high among ethnic Miao, Buyi and Dong populations from Guizhou, and there was a significant difference between the three.

Objective: To investigate allelic frequencies of interluekin-10 (IL-10) gene promoter in Miao, Dong and Buyi ethnics of Guizhou., Methods: TaqMan MGB-based real-time PCR was used to determine the genotypes of IL-10 -819 and IL-10 -592 in 589 Miao, Dong and Buyi ethnics of Guizhou., Results: The allelic frequency of IL-10 -819 in Miao ethnics was significantly different from those in Dong or Buyi ethnics. Allelic frequencies of IL-10 -592 in Miao ethnics was significantly different from those in Dong or Buyi ethnics. In Miao, Dong and Buyi ethnics, the distributions of genotype frequencies of IL-10 -819 and IL-10 -592 were statistically different from Han ethnics from Guizhou and Taiwan of China as well as South Koreans., Conclusion: There is a heterogeneity in the frequencies of polymorphisms of IL-10 promoter among different ethnic groups.

Objective: To investigate the association between both regulated upon activation normal T cell expressed and secreted (RANTES) -403G/A, -28C/G gene polymorphism and the susceptibilities to hepatitis B virus (HBV) infection, among people with Dong and Han ethnicities, in Guizhou., Methods: A total of 229 individuals with HBV persistence infection, 161 HBV clearanced patients and another 200 controls were recruited to conduct a case-control study among residents with Dong or Han ethnicities. Allelic frequencies of both RANTES-403G/A and -28C/G were identified by TaqMan-MGB probe., Results: Both RANTES-403G/A and -28C/G polymorphism in the HBV-persistent group, when compared to the HBV-clearances group, no significant difference was found (P > 0.05)., Results: from the univariate analysis showed that subjects carrying -403AG and -28GG genotype had higher risk on the susceptibility to HBV persistence infection. The distributions of RANTES-28C/G gene polymorphism between Dong minority and Han ethnicities regarding HBV persistence showed statistically significant difference (P < 0.05). There was no difference on the distributions of RANTES-403G/A gene polymorphism between Dong minority and Han ethnicities., Conclusion: Patients that carrying both RANTES-403AG and -28GG genotype had higher risk on the persistence to HBV, while RANTES-403A had contributed to the clearance of HBV infection.

Objective: To investigate the association between interleukin-10 (IL-10) gene promoter microsatellite polymorphisms and the susceptibility to hepatitis B virus infection in Han, Yi and Yao ethnicities in GuiZhou province., Methods: 500 volunteers were selected from Guizhou province. Allelic frequency of IL-10.G and IL-10.R loci was identified by short tandom repeat polymerase chain reaction. The relativity between allelic frequency and HBV infection was analyzed., Results: Genotype data from H-W analysis on all the IL-10 polymorphisms indicated that it was a random distribution. Very high HBV infection rates were found in the native ethnic minorities of Guizhou province. The overall HBV infection rate among the total population was 67.00%, with the HBV infection rates of Yi nationality in Weining, Yi nationality in Qianxi, Yao nationality in Libo and Han nationality in Libo as 51.85%, 42.86%, 79.52% and 84.30%, respectively. The polymorphisms distribution of IL-10.G and IL-10.R were statistically different among the ethnic groups (P < 0.05). The polymorphisms distribution of IL-10.R had no significant difference between HBV infection group and non-infection group, as well as among HBV natural removal group and non-infected group in all the ethnic groups. The frequency of IL-10.G 459 bp (19CA) was significantly higher in non-infection group than in the infected group (P < 0.05). The frequency of IL-10.G 471 bp (25CA) was significantly higher in the non-infection group than in the HBV natural removal group (P < 0.05). The polymorphisms distribution of IL-10.G did not show significant difference between the HBV infection group and the HBV natural removal group in all the ethnic groups. We did not find any differences in allelic and genotypic frequencies of IL-10.G between infection group and non-infection group in Yi nationality in Weining, and Yao nationality in Libo (P > 0.05), as well as HBV natural removal group and non-infected group (P > 0.05)., Conclusion: The polymorphisms distribution of IL-10.R and IL-10.G did not show significant difference in Yi, Yao and Han ethnics population living in Guizhou province. IL-10.G seemed to influence the susceptibility of HBV infection in Han, Yao and Yi ethnics population of Guizhou province.

Objective: To investigate the association of IL-10 gene promoter polymorphism with susceptibility to hepatitis B viral infection in Han, Yi and Yao ethnic groups from Guizhou province., Methods: Five hundred volunteers from Guizhou province were selected to undertake PCR-RFLP for detection of IL-10 gene promoter -592 polymorphism., Results: The genotypic distributions of IL-10-592 were 32.53%-51.43% (AA), 40.74%-54.82% (AC), 5.79%-18.52% (CC) whereas the allelic frequencies were 59.94%-72.38% for the A allele, and 27.62%-40.06% for the C allele in Han, Yi and Yao ethnic from Guizhou. The distributions of allele and genotype frequencies of IL-10-592 were statistically different between Yao ethnic in Libo and Yi ethnic in Qianxi, Yao ethnic in Libo and Han ethnic in Libo,Yi ethnic in Qianxi and Yi ethnic in Weining,Yi ethnic in Weining and Han ethnic in Libo (P < 0.05). IL-10-592 polymorphism was associated with HBV infection in Yi ethnic in Qianxi and the whole population., Conclusion: IL-10-592 gene polymorphisms influenced the susceptibility to HBV infection in Han, Yao, Yi sub-populations in Guizhou. Result of the study suggested that IL-10-592 gene polymorphisms might serve as a risk factor to HBV infection.