Genetic polymorphisms and mutation rates of 27 Y-chromosomal STRs in a Han population from Guangdong Province, Southern China.

In this study, we collected blood samples from 1033 father-son pairs of a Han population from Guangdong Province, Southern China, of which 1007 fathers were unrelated male individuals. All together, 2040 male individuals were analyzed at 27 Y-chromosomal short tandem repeats (Y-STRs) with Yfiler(®) Plus system. A total of 1003 different haplotypes were observed among 1007 unrelated fathers, with the overall haplotype diversity (HD) 0.999992 and discrimination capacity (DC) 0.996. The gene diversity (GD) values for the 27 Y-STR loci ranged from 0.4400 at DYS438 to 0.9597 at DYS385a/b. 11 off-ladder alleles and 25 copy number variants were detected in 1007 males. Population relationships were analyzed by comparison with 19 other worldwide populations. With 27,920 allele transfers in 1033 father-son pairs, 124 mutation events occurred, of which 118 were one-step mutations and 6 were two-step mutations. Eleven father-son pairs were found to have mutations at two loci, while one pair at three loci. The estimated locus-specific mutation rates varied from 0 to 1.74×10(-2), with an average estimated mutation rate 4.4×10(-3) (95%CI: 3.7×10(-3) to 5.3×10(-3)). Mutations were most frequently observed at three rapidly mutating Y-STRs (RM Y-STRs), DYS576, DYS518 and DYS627. However, at DYS570, DYS449 and DYF387S1 loci, which were also described as RM Y-STRs, the mutation rates in Guangdong Han population were not as high as estimated in other populations.

[Study on UV and H2O2 combined inactivation of E. coli in drinking water].

The inactivation effect of E. coli with both UV irradiation and hydrogen peroxide disinfection individually and in different combination modes was investigated. The results showed that hydrogen peroxide alone caused hardly any inactivation of E. coli. Only 0.02 lg inactivation was achieved by hydrogen peroxide with concentration of 20 mg x L(-1) and contact time of 30 min. UV irradiation was able to inactivate E. coli to a certain extent. The inactivation reached 4.51 lg at a UV dose of 10 mJ x cm(-2). The combination of UV and H2O2 could significantly improve the inactivation effect and the different combination modes affected the inactivation effect. The inactivation effect of UV-H2O2 was better than that of H2O2 -UV. The inactivation was increased by 0.09, 0.35, 0.38, 0.68 lg and 0.01, 0.07, 0.14, 0.53 lg when compared to the treatment with solely UV irradiation, respectively, at UV dose of 5 mJ x cm(-2) with hydrogen peroxide at contact time of 2.5, 5, 10, 20 minutes. UV/H2O2 achieved better results than sequential disinfection. The inactivation was enhanced by 0.43 lg and 0.58 lg when compared to UV-H2O2 and H2O2-UV, respectively, at UV dose of 5 mJ x cm(-2) with hydrogen peroxide at contact time of 20 minutes. The inactivation of E. coli increased with the enhancement of UV radiation intensity.

Photochemical degradation of ciprofloxacin in UV and UV/H2O2 process: kinetics, parameters, and products.

Photochemical degradation of fluoroquinolone ciprofloxacin (CIP) in water by UV and UV/H2O2 were investigated. The degradation rate of CIP was affected by pH, H2O2 dosage, as well as the presence of other inorganic components. The optimized pH value and H2O2 concentration were 7.0 and 5 mM. Carbonate and nitrate both impeded CIP degradation. According to liquid chromatography-tandem mass spectrometry analysis, four and 16 products were identified in UV and UV/H2O2 system, respectively. Proposed degradation pathways suggest that reactions including the piperazinyl substituent, quinolone moiety, and cyclopropyl group lead to the photochemical degradation of CIP. Toxicity of products assessed by Vibrio qinghaiensis demonstrated that UV/H2O2 process was more capable on controlling the toxicity of intermediates in CIP degradation than UV process.

[Comparison study of enhanced coagulation on humic acid and fulvic acid removal].

Enhanced coagulation effects of four coagulants, such as aluminium sulfate, ferric chloride, aluminium polychloride and poly-ferric chloride, were examined, with an emphasis on pH, turbidity, Ca+ and relative contents of humic acid and fulvic acid. The result showed that the removal efficiency of four kinds of coagulant for humic acid was higher than that for fulvic acid. Compared with aluminium polychloride and poly-ferric chloride, aluminium sulfate and ferric chloride possessed a better coagulation effect. At the coagulant dosage of 40 mg x L(-1), ferric chloride, aluminium sulfate, poly-ferric chloride and aluminium polychloride removed fulvic acid from 10 mg x L(-1) to 3.22 mg x L(-1), 4.34 mg x L(-1), 5.85 mg x L(-1) and 4.86 mg x L(-1) respectively, while the four coagulants removed humic acid from 10 mg x L(-1) to 1.13 mg x L(-1), 2.13 mg x L(-1), 3.44 mg x L(-1) and 2.50 mg x L(-1) respectively in water. At pH between 5.5 and 6.5, aluminium sullfate and ferric chloride had the best coagulation effect. The coagulant had the lower efficiency with increase of organic carbon in water. Especially, the content ratio of fulvic acid and humic acid was above 0.4, the coagulation effect markedly decreased. Turbidity has a little influence on organic carbon removal rate. With the concentration of Ca2+, the removal efficiency of humic acid and fulvic acid increased.

[Genetic polymorphisms of six Y chromosome short tandem repeat loci in Chinese Korean ethnic group].

OBJECTIVE: To determine the allelic sequences and genetic polymorphism of six short tandem repeats (STRs) loci on Y chromosome, including DYS441, DYS442, DYS443, DYS444, DYS445 and DYS446 in Chinese Korean ethnic males from Yanbian region of Jilin province, China, and to construct a preliminary database. METHODS: Allele frequencies of the six STR loci in 205 Chinese Korean ethnic individuals were analyzed by multiplex polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE). RESULTS: Respectively, 8, 7, 7, 5, 6 and 9 alleles were detected for each of the locus. Together they have formed 151 haplotypes, with a diversity of 0.9937. CONCLUSION: The six STR loci included in this study were found to be highly polymorphic, and may provide useful markers for genetic analysis.

[Comparison of H2O2 and UV processes on the inactivation efficiency of Microcystic aeruginosa].

Setting Microcystic aeruginosa as study subject, the inactivation efficiency and its effect on photosynthetic activity by H2O2 and UV processes were investigated. The results showed that the inactivating efficiency increased with H2O2 dosage in the range of 0-2 mmol x L(-1), and the photosynthetic activity decreased with it gradually, but the efficiency wasn't enhanced when the dosage exceeded 2 mmoL x L(-1). The inactivation by UV process was high. Under the algae concentration of 35 x 10(8) cells/L, UV dosage of 91.8 mJ/cm2 was enough to inhibit its growth by 7d; UV process was superior to H2O2 in terms of photosynthetic activity, also the parameters could be fitted exponentially well; To guarantee high removal of algae, H2O2 must be dosed excessively, so UV254 of algae solution would be higher than that of UV process.

[Genetic polymorphisms of six X-short tandem repeats loci in Chinese Korean].

OBJECTIVE: To investigate the genetic polymorphisms of DXS7132, DXS6854, DXS6797, DXS9898, DXS8378 and GATA31E08 short tandem repeats (STRs) loci in Chinese Korean ethnic group of Yanbian, Jilin, and to construct a preliminary database. METHODS: The allele frequencies of the six STRs loci in Chinese Korean ethnic individuals were analyzed by multiplex polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE). RESULTS: Total of 8, 6, 8, 8, 5 and 10 alleles were observed in each locus respectively. All loci (in female) met Hardy-Weinberg equilibrium (P > 0.05). The statistical analysis of the 6 STR loci showed the heterozygosities were more than 0.4660, the polymorphic information contents (PIC) were more than 0.5293, the haplotype diversity were more than 0.9993, power of discrimination (PD) in females and males were more than 0.7737 and 0.6107, respectively. CONCLUSION: The results showed that, all the 6 STR loci in this study were found to have high heterozygosity and polymorphic information content, so they could provide useful markers for genetic purposes. These results could serve as valuable data to enrich the Chinese Korean ethnic group genetic database and play an important role in genetic study of Chinese population.

[Oxidization characteristic of chlorine on the biofilm in simulated drinking water distribution system].

In the article, the inactivation effect of chlorine on E. coli biofilm and the influence of chlorine oxidization on the contents of assimilable organic carbon (AOC), microbially available phosphorus (MAP) and bacterial regrowth potential (BRP) was investigated in the simulated drinking water distribution system. Results showed that chlorine resulted in more efficient reduction on suspended E. coli than did in biofilm. The inactivation effect of E. coli was influenced by chlorine concentration. Likewise, higher chlorine concentration resulted in more E. coli inactivation rate at the same CT (chlorine concentration multiply by time) value, when biofilm was oxidized by chlorine. Concentrations of AOC and MAP in bulk water increased owing to organic substance dissolved from biofilm. The AOC concentration increased from 20.78 microg/L to 120.17 microg/L, and the MAP was increased from 0.11 microg/L to 0.17 pg/L, and the Chlorine oxidization enhanced BRP concentration in the bulk water. BRP reached maximum at 1.10 x 10(7) CFU/mL when chlorine concentration was 1.0 mg/L, CT value was 100 mg x min/L.

[Mechanism of natural organic matter removal by potassium permanganate composite enhanced coagulation].

Streaming current technique, fluctuation of transmitted light technique, molecular weight distribution and XAD resin adsorption technique were used to study the mechanism of natural organic matter removal by potassium permanganate composite (PPC) enhanced coagulation. Results showed that natural organic matter removal efficiency increased 13% by 0.75 mg/L potassium permanganate composite enhanced coagulation compared with that of alum coagulation alone. Streaming current indicated that potassium permanganate composite decreased the organic matter stability by reducing the surface negative charge, and the SC value increased from 55.2 to 61.4, 69.6 and 87.0 by addition of 0.50, 0.75 and 1.0 mg/L PPC. Coagulation index R indicated both nascent manganese dioxide and subsidiaries played an important role in potassium permanganate composite enhanced coagulation process. Potassium permanganate composite enhanced coagulation increased the removal efficiency of lower molecular weight and hydrophilic organic matter compared with alum coagulation, and hydrophilic organic matter can be reduced from 1.9 mg/L to 1.32 mg/L by the addition of 0.75 mg/L potassium permanganate composite.

[Mitochondrial DNA coding region 3954-4506 polymorphism in Korean Chinese population].

OBJECTIVE: To investigate the sequence polymorphism of mtDNA coding region encompassing nt3954-4506 in the Korean Chinese population of Yanbian area. METHODS: Polymerase chain reaction (PCR) and direct sequencing method were used to detect the haplotype distribution of mtDNA coding region in 198 Korean Chinese individuals. RESULTS: Twenty-one haplotypes were observed in the 198 unrelated individuals. The genetic diversity was 0.5906 and the random match probability was 0.4124. Compared with the Andersonos sequence, 19 nucleotide variants were found, of which 14 were previously registered in MITOMAP, and 5 were novel. CONCLUSION: The obtained data suggest that these sequence polymorphisms are valuable genetic markers for personal identification when combined with mtDAN control region investigation, thus could be used as basic data for the forensic application in Korean Chinese population.

[Effect analysis on MOH/WHO/Luxembourg project of strengthening cold chain and childhood immunization service quality project in Qinghai province].

OBJECTIVE: To improve the cold chain systematic management and the quality of immunization through implementing MOH-WHO-Luxembourg project of strengthening cold chain and childhood immunization service quality in Qinghai province. METHODS: Analysis and comparison of relevant information of cold chain equipment, disease surveillance and immunization management. RESULTS: 47% township had transportation facility for immunization programs, 61% township hospital cold-chain equipment was renewed, 30% township hospitals cold-chain equipment updated. Vaccination safe injection has improved. 3554 staffs have been trained, the qualified rate > 98%. The measles incidence of children who are under five years dropped from 40/10 million in 2003 to 6.4/10 million in 2006. CONCLUSION: The imunization service quality had been improved effectively through the project implementation.

[Study on the probability of hepatitis B virus infection at public service places].

OBJECTIVE: To provide data for the control and prevention of hepatitis B and HBV surface antigen (HBsAg) status among the appliances and practitioners working in the public service places. METHODS: 63 beauty parlors, barber shops and bathing centers selected under stratified randomization sampling method and 682 workers were investigated through questionnaire. HBsAg from th e appliances of the public service places and employee was detected by RIA. RESULTS: Two main sanitizing modes that including alcohol cleaning (34.60%) and ultraviolet light disinfection (30.79%) were used. The rates of testing on HBsAg among the appliances were 2.13% at the public service places, and were 0.63%, 2.67% and 3.70% in large-, medium- and small-sized appliances respectively. The rate of testing on HBsAg on large-, medium- and small- sized appliances were statistically different (chi2 = 6.68, P < 0.05). The positive rates of HBsAg on the appliances of beauty parlors, barbering shops and footbath inns were 2.97%, 0.61% and 3.42% respectively. People working in different service sites had different rates of HBsAg: those who worked at the 'acne needle' and the forceps were 5.13% and 4.17%. The positive rate of HBsAg among the workers in the public service places was 7.13%. The rates of HBsAgamong the workers in large-, medium- and small-sized public service places were 7.34%, 8.33% and 2.94% respectively. The rates of HBsAg among the workers in beauty parlors, barbering shops, footbath inns and bathing centers were 9.01%, 6.37%, 4.35% and 7.29% respectively. HBsAg positive rates were different among the workers working at different service sites: 13.33% at tattoo business, 12.68% in pedicles workers and 8.03% in massagists. CONCLUSION: It is important to improve the sanitizing management of the appliances used in the public service places and to improve the knowledge, attitude, as well as practice of vaccination on hepatitis B among those populations.

[Characteristic of natural organic matter removal by ferric and aluminium coagulation].

Natural organic matter removal efficiency and characteristic by ferric chloride and aluminium sulphate were studied. Results showed that ferric chloride was effective in natural organic matter removal when coagulant dosage was higher than 15 mg/L, while aluminium was effective at lower dosage. The TOC of water was reduced to 4.19 mg/L and 9 mg/L at a dosage of 10 mg/L for aluminium sulphate and ferric chloride respectively, while TOC was reduced to 2.44 mg/L and 1.69 mg/L at the dosage of 20 mg/L. Ferric chloride decreased pH sharply than aluminium sulphate which made hydrolysate more positive and attachable for natural organic matter. UV254 and SUVA results showed that ferric chloride removed more conjugate structure materials and unsaturated band contents than aluminium. Ferric chloride was more effective in reducing lower molecular weight organic matter and hydrophilic substances than aluminium, when the dosage of coagulant was 20 mg/L, the removal efficiency of relative molecular weight below 10 000 was 16.4% and 6.1% respectively, while aluminum was more effective in high molecular weight matter removal than ferric chloride.

[Effect of chloramines disinfection for biofilm formation control on copper and stainless steel pipe materials].

Two rotating annular bioreactors (RABs) with copper and stainless steel pipe materials were adopted in the study, the effects of these two pipe materials and chloramines disinfection on biofilms formation in drinking water distribution system were evaluated. The maximum viable bacterial number in biofilm of copper and stainless steel reached 5.5 x 10(3) CFU/cm2 and 2.5 x 10(5) CFU/cm2 at 18th and 21st day without chloramines, and the viable bacterial number at the apparent steady state was 1.0 x 10(3) CFU/cm2 and 1.3 x 10(5) CFU/cm2 respectively. It was obvious that the biomass on copper materials was lower than that of the stainless steel. The maximum viable bacterial on copper and stainless steel under chloramines was 5.0 x 10(2) CFU/cm2 and 5.0 x 10(4) CFU/cm2, which was one order of magnitude lower than that of without chloramines, and its number was 10 CFU/cm2 and 3.5 x 10(4) CFU/cm2 at the steady state. These results illustrated that chloramines had apparent ability in controlling biomass when the biofilm was on steady states, especially for copper material. There was exponential relationship between biomass in biofilm and residue chloramines, which meant less biomass with more chloramines, synergistic effects were observed between chloramines and copper materials on biomass in biofilms inactivation.

[Genetic polymorphisms of short tandem repeat loci D4S2368, D6S1043, D9S925 from Korean ethnic group of JiLin].

OBJECTIVE: To understand the allele structure and genetic polymorphism at D4S2368, D6S1043, D9S925 short tandem repeat (STR) loci in Korean ethnic group of Jilin, and to construct a preliminary database. METHODS: The allele frequencies of the three STRs loci in 310 unrelated individuals from Korean ethnic individuals were analyzed by polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE). RESULTS: Seven, thirteen, and nine alleles were observed at D4S2368, D6S1043, and D9S925 loci, respectively, and all loci met Hardy-Weinberg equilibrium (except D6S1043). The statistical analysis of 3 STR loci showed the heterozygosities were more than 0.717, the polymorphic information contents (PIC) were more than 0.670; the combined power of discrimination (PD) and the power of exclusion (PE) were more than 0.9995 and 0.952 respectively. CONCLUSION: The three loci in this study are found to have high heterozygosity and polymorphic information content, so they can provide useful markers for genetic purposes. These results could serve as valuable data to enrich the Korean ethnic group genetic database and play an important role in Chinese population genetic application.

Effects of UV intensity and water turbidity on microbial indicator inactivation.

The effects of UV intensity and turbidity on selected microbial indicator inactivation were investigated. Results showed that UV disinfection was effective in killing all the selected microbial indicators, the resistance order of the microorganisms was as follows: MS-2 coliphage > Bacillus subtilis > E. coli > Staphylococcus aureus and Candida albicans. UV intensity had influence on the inactivation of all the microorganisms, high UV disinfection efficency was obtained with higher UV intensity. Turbidity had impact on the bacteria inactivation rate, but there was no evidence that turbidity had any negative contribution to MS-2 coliphage. Under the same UV dosage, higher UV intensity could overcome the negative influence of turbidity on UV performance, enhanced microorganism inactivation effect in turbidity water.

[Effects of potassium permanganate on natural organic matter chlorination activity].

Effects of potassium permanganate (PP) oxidation on natural organic matter(NOM) chlorination activity was studied in the article. Natural organic matter was separated into humic acid (HA), fulvic acid(FA), hydrophilic acid(HPIA) and non-hydrophilic acid (HPI-NA) fraction four fractions by XAD resin adsorption technique. Potassium permanganate oxidation alone increased HA and HPIA chlorination activity and decrease that of FA and HPI-NA. The chlorination activity of HA and HPIA were increased by 39.3% and 13.8% by 0.75 mg/L. potassium permanganate, but the chlorination activity of FA and HPI-NA were decreased by 33.6% and 46.9%. SUVA results showed that potassium permanganate increase FA and HPIA unsaturated band contents, and decreased that of FA and HPI-NA. Compared with coagulation, potassium permanganate combined with coagulation can decrease the trihalomethanes of HA, FA, HPIA and HPI-NA by 9.1,15.7,7.2 and 14.7 per cent compared with that of coagulation alone.

[Synergistic disinfection of Bacillus subtilis spores by UV irradiation and chlorine].

The inactivation effect of Bacillus subtilis spores was studied, both UV irradiation and chlorine disinfection individual and combined application process was examined with laboratory water samples. Results show that only 0.53 lg reduction was achieved by chlorine with CT value of 300 (mg x min)/L, UV irradiation is more effective than that of chlorination, at a UV dose of 40mJ/cm2 results in 3.3 lg reduction. Up to 6.2 lg reduction are achieved with a UV dose of 40mJ/cm2 following by chlorine with CT value of 300 (mg x min)/L. The calculation from the Berenbaum formula verified that the effect of the combined applications of UV irradiation and chlorine in inactivatiing Bacillus subtilis is a kind of synergistic effect.