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Objective To understand the water quality of self-supply wells in four provinces of northern China (Heilongjiang, Beijing, Inner Mongolia and Tibet), so as to provide a reference for supervision and management of self-supply wells. Methods Water were sampled from 233 self-supply wells in four northern provinces of China according to standard examination methods for drinking water (GB/T 5750-2006). In total, The samples were tested for 27 kinds of water quality parameters involving sensory properties, chemistry, bacteriology and toxicology, and then evaluated. Results The total unqualified rate of water quality in self-supply well water in four northern provinces of China was 52.36%. The water quality varied greatly among provinces. As for Heilongjiang, the main unqualified indicators of self-supply wells water involved turbidity, visible to the naked eye, manganese, arsenic and nitrate. In relation to Beijing, these referred to the nitrate and microorganism. In case of Inner Mongolia province, these included sulfate and fluoride. With reference to Tibet, these were zinc and chloride. Conclusions To ensure the safety of drinking water for residents, the management, disinfection and purifying measures of self-supply wells should be strengthened basing on their regional differences and water quality characteristics.
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Objective To find out about the sanitary conditions of drinking water along the border line of Inner Mongolia via safety evaluation of drinking water along the border line of Inner Mongolia.Methods 108 samples of drinking water along the border line of Inner Mongolia(70 samples of self-supply source water,21 ones of self-supply tap water and 17 ones of municipal tap water)were collected.Hygienic evaluation of sensory indexes, normal chemical indexes, toxicological indexes and microbiology indexes of water quality was performed according to hygienic standards for drinking water(GB 5749—2006).Results 58 samples were qualified with a total qualified rate of 53.7%.The unqualified rate of the total number of coliforms was the highest(20.4%),followed by fluoride(19.4%).As for deep wells, shallow wells and surface water,there was no statistically significant difference.Compared with municipal tap water,the unqualified rate of self-supply water(28.6%)was higher(17.7%).Conclusion The qualified rate along the border line of Inner Mongolia of drinking water is low.Treatment and disinfection facilities for drinking water,detection devices of water quality are needed.The cleaning and disinfection of storage tanks should be performed periodically in oder to prevent waterborne infectious diseases.
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<p><b>OBJECTIVE</b>To detect the single nucleotide polymorphism (SNP) of chemokine regulated upon activation, normal T cell expressed and secreted (RANTES) promoter and first intron of asymptomatic, human immunodeficiency virus 1 (HIV-1) infected individuals of in Han Chinese and evaluate the influence on HIV-1 infection by variants.</p><p><b>METHODS</b>Case-control study was adopted, Genotypes of RANTES promoter -403 and -28 from 538 samples and RANTES first intron In1.1 from 300 samples of Han Chinese were detected by DNA sequencing or by polymerase chain reaction-restriction fragment length polymorphism.</p><p><b>RESULTS</b>There were six genotypes of RANTES promoter -403 and -28 found in Han Chinese group. The distribution of genotypes was AC/AC 12.4%, AC/AG 3.5%, AC/GC 29.2%, AG/GC 10.9%, GC/GC 42.1%, AG/AG 1.5%. The haplotypes was GC 62.7%, AC 28.7%, AG 8.6%. Compared with AC/AC, Odd ratio (OR) of RANTES genotypes AC/AG, AC/GC, AG/GC, GC/GC was associated with weaker reduced susceptibility to HIV-1 infection. However, there were no significant contents of the allele frequencies between people living with HIV-1 and healthy individuals. The distribution of RANTES In1.1 alleles were T/T 71.0%, C/T 19.9%, C/C 9.1% and haplotypes were RANTES In1.1T 81%, In1.1C 19%, respectively; There were significant differences of RANTES In1.1 between people with HIV-1 infection and healthy individuals in males. The In1.1C-bearing genotypes would increase susceptibility to HIV-1 infection but no significant differences in females were found. Strong linkage disequilibrium was observed between all of the three RANTES SNPs.</p><p><b>CONCLUSION</b>The two -403A/G, -28C/G variants in RANTES promoter region and intron In1.1 T/C mutation genotype were found to be associated with the genetic susceptibility to HIV-1 infection among the Han Chinese. However, the In1.1C allele or its haplotypes in RANTES intron 1 displayed a stronger dominant association with HIV-1 infection in males.</p>