2010 Vol. 23, No. 3
2010, 23(3): 167-172.
Objective To predict neural tube birth defect (NTD) using support vector machine (SVM). Method The dataset in the pilot area was divided into non overlaid training set and testing set. SVM was trained using the training set and the trained SVM was then used to predict the classification of NTD. Result NTD rate was predicted at village level in the pilot area.The accuracy of the prediction was 71.50% for the training dataset and 68.57% for the test dataset respectively. Conclusion Results from this study have shown that SVM is applicable to the prediction of NTD.
2010, 23(3): 173-179.
Objective To evaluate the present Chinese body mass index (BMI) criteria with body fat percentage (BF%) in determining obesity in Chinese population. Methods A total of 4 907 subjects (age: 20-90 yrs) were enrolled in the baseline survey of a longitudinal epidemiological study, and 2 638 of them were reevaluated in 5.5 years later. The Chinese BMI and WHO BF% were used to define obesity, respectively. Results The diagnostic agreement between the Chinese BMI and WHO BF% definitions for obesity was poor for both men (kappa: 0.210, 95% CI: 0.179-0.241) and women (kappa: 0.327, 95% CI: 0.296-0.358). However, BMI had a good correlation with BF% both in men (r: 0.785, P<0.01) and women (r: 0.864, P<0.01). The age and sex-adjusted relative risks (RR) for incidence of type 2 diabetes (T2DM) were significantly higher in subjects with intermediate BF% (BF%:20.1%-25% for men, 30.1%-35% for women) (RR: 2.35, 95% CI: 1.23-4.48) and high BF%(BF%>25% for men and >35% for women)(RR: 2.89, 95% CI: 1.43-5.81), or in subjects with high BMI (BMI≥28 kg/m2) (RR: 2.46, 95% CI: 1.31-4.63) when compared to those with low BF% (BF%≤20% for men and≤30% for women) or low BMI (BMI<24 kg/m2) respectively. No difference in risk could be found in those with intermediate BMI (BMI: 24-27.9 kg/m2) (RR: 1.44, 95% CI: 0.86-2.40), as compared to those with low BMI (BMI<24 kg/m2), whose BF% ranged widely from 7.8 to 50.3%. Conclusion BMI was correlated with BF%. Both BMI and BF% were associated with high risk for T2DM. However, BMI had its limitations in the interpretation of subjects with BMI between 24 and 27.9 kg/m2.
Report on Childhood Obesity in China (8): Effects and Sustainability of Physical Activity Intervention on Body Composition of Chinese Youth
2010, 23(3): 180-187.
Objectives To determine whether a large-scale physical activity intervention could affect body composition in primary school students in Beijing, China. Methods The study design was one-year cluster randomized controlled trial of physical activity intervention (20 min of daily exercise in the classroom) with an additional year of follow-up among 4 700 students aged 8-11 years at baseline. Results After the one-year intervention, BMI increased by 0.56 kg/m2 (SD 1.15) in the intervention group and by 0.72 kg/m2 (SD 1.20) in the control group, with a mean difference of-0.15 kg/m2 (95% CI: -0.28 to -0.02). BMI z score decreased by -0.05 (SD 0.44) in the intervention group, but increased by 0.01 (SD 0.46) in the control group, with a mean difference of-0.07 (-0.13 to -0.01). After another year of follow up, compared to the control group, children in the intervention group had significantly lower BMI (-0.13, -0.25 to -0.01), BMI z score (-0.05, -0.10 to -0.01), fat mass (-0.27 kg, -0.53 to -0.02) and percent body fat (-0.53, -1.00 to -0.05). The intervention had a more pronounced effect on weight, height, BMI, BMI z score, and body composition among obese children than among normal weight or overweight children. Compared to the control group, the intervention group had a significantly higher percentage of children who maintained or reduced their BMI z score at year 1 (P=0.008) and year 2 (P=0.04). Conclusions These findings suggest that 20 min of daily moderate to vigorous physical activity during the school year is a feasible and effective way to prevent excessive gain of body weight, BMI, and body fatness in primary school students.
Molecular Characterization of Drug-Resistant Beijing Family Isolates of Mycobacterium Tuberculosis from Tianjin,China
2010, 23(3): 188-193.
Objective Tuberculosis remains a severe public health issue,and the Beijing family of mycobacterium tuberculosis (M.tuberculosis) is widespread in East Asia,especially in some areas in China,like Beijing and Tianjin.This study aimed at determining the mutation patterns of drug-resistant Beijing strains of M.tuberculosis isolated from Tianjin,China.Methods A total of 822 M.tuberculosis isolates were screened for drug resistance by an absolute concentration method and the genotype was identified by PCR.169 drug-resistant isolates of the Beijing family were analyzed for the potential mutations in the rpoB,katG,inhA promoter region and in rpsL,rrs and embB genes,which are associated with resistance to rifampin (RFP),isoniazid (INH),streptomycin (SM) and ethambutul (EMB) respectively by PCR and DNA sequencing.Results Fifty-eight out of 63 RFP-resistant isolates were found to carry the mutations within the 81-bp RFP resistance determining region (RRDR) of the rpoB gene and the most frequent mutations occurred at codon 531 (44.4%),526 (28.6%),and 516 (7.9%) respectively.16 mutation patterns affecting 12 different codons around the RRDR of rpoB were found.Of 116 INH-resistant isolates,56 (48.3%)had the mutation of katG 315 (AGC→ACC) (Ser→Thr),3 (2.6%) carried S315N (AGC→AAC) and 27 (16.0%) had the mutation of inhA-15A→T.84 out of 122 SM-resistant isolates (68.9%) displayed mutations at the codons 43 or 88 with AAG→AGG (Lys→Arg) of the rpsL gene and 22 (18.0%) with the mutations at positions 513A→C,516C→T or 905 A→G in the rrs gene.Of 34 EMB-resistant isolates,6 had mutation with M306V (ATG→GTG),3 with M3061 (ATG→ATT),1 with M3061 (ATG→ATA),1 with D328Y (GAT→TAT),1 with V348L (GTC→CTC),and 1 with G406S (GGC→AGC) in the embB gene.Conclusion These novel findings extended our understanding of resistance-related mutations in the Beijing strains of M.tuberculosis and may provide a scientific basis for development of new strategies for diagnosis and control of tuberculosis in China and other countries where Beijing swains are prevalent.
Precise Microdeletion Detection of Prader-Willi Syndrome with Array Comparative Genome Hybridization
2010, 23(3): 194-198.
Objective Prader-Willi Sydrome (PWS) is a human disorder related to genomic imprinting defect on 15q11-13.It is characterized by a series of classic features such as hypotonia,hyperphagia,obesity,osteoporosis,typical facial and body dysmorphosis,hypogonadism,mental and behaviour disorders.Our study was designed to precisely detect the microdeletions,which accounts for 65%-70% of the PWS.Methods Physical and laboratory examinations were firstly performed to diagnose PWS clinically,and to discover novel clinical features.Then the patient was screened with bisulfite-specific sequencing and precisely delineated through high-density array CGH.Results With the bisulfite-specific sequencing,the detected CpG island in the PWS critical region was found homozygously hypermethylated.Then with array CGH,a 2.22 Mb type II microdeletion was detected,covering a region from MKRN3,MAGEL2,NDN,PWRN2,PWRN1,Cl2orf2,SNURF-SNRPN,C/D snoRNAs,to distal of UBE3A.Conclusions Array CGH,after the fast screening of Bisulfite-specific sequencing,is a feasible and precise method to detect microdeletions in PWS patients.A novel feature of metacarpophalangeal joint rigidity was also presented,which is the first time reported in PWS.
Effects of Exposure to GSM Mobile Phone Base Station Signals on Salivary Cortisol,Alpha-Amylase,and Immunoglobulin A
2010, 23(3): 199-207.
Objective The present study aimed to test whether exposure to radiofrequency electromagnetic fields (RF-EMF) emitted by mobile phone base stations may have effects on salivary alpha-amylase,immunoglobulin A (IgA),and cortisol levels.Methods Fifty seven participants were randomly allocated to one of three different experimental scenarios (22 participants to scenario 1,26 to scenario 2,and 9 to scenario 3).Each participant went through five 50-minute exposure sessions.The main RF-EMF source was a GSM-900-MHz antenna located at the outer wall of the building.In scenarios 1 and 2,the first,third,and fifth sessions were "low" (median power flux density 5.2 μW/m2) exposure.The second session was "high" (2126.8 μW/m2),and the fourth session was "medium" (153.6 μW/m2) in scenario 1,and vice versa in scenario 2.Scenario 3 had four "low"exposure conditions,followed by a "high" exposure condition.Biomedical parameters were collected by saliva samples three times a session.Exposure levels were created by shielding curtains.Results In scenario 3 from session 4 to session 5 (from "low" to "high" exposure),an increase of cortisol was detected,while in scenarios 1 and 2,a higher concentration of alpha-amylase related to the baseline was identified as compared to that in scenario 3.IgA concentration was not significantly related to the exposure.ConclusionsRF-EMF in considerably lower field densities than ICNIRP-guidelines may influence certain psychobiological stress markers.
2010, 23(3): 208-212.
Objective Nitrobenzene extraction enhanced by salting-out effect was employed to recover aniline from wastewater at25℃.Method Batchwise experiments were conducted to elucidate the influence of various operating variables on the extracting performance,including acidity of wastewater,initial aniline concentration,ratios of solvent to wastewater,extraction stages,concentrations and different types of inorganic salts,such as NaCl,KCl,Na2SO4,CaCl2 and K2SO4.Results Nitrobenzene with a concentration of 20% and a pH value of 9.1 at the temperature of 25℃ together with NaCl of a concentration of 14 wt.% realized nearly 100% aniline recovery at the fifth stage of wastewater treatment.Conclusions High pH values and volume ratios of nitrobenzene/wastewater are more suitable for recovery of aniline.In addition,recovery of aniline is significantly elevated with increase of the concentration of salts,whose promoting effects are in the following order:NaCl>Na2SO4>K2SO4>CaCl2>KCl on the weight basis of wastewater.Furthermore,aniline in wastewater can be almost completely recovered by five-stage sequential nitrobenzene extraction,which is promoted continuously by the salting-out effect.
2010, 23(3): 213-218.
Objective To study the characteristics of a bioflocculant named MBF7 produced by Penicillum strain HHE-P7 and the effects of cultivation conditions on bioflocculant production.Methods The chemical group in the bioflocculant molecules was shown by Fourier transform infrared(FTIR)spectra,and the average molecular weight of MBF7 was estimated by gel permeation chromatography.The effects of medium components on bioflocculant production and flocculating activity were studied.Results Phospho-,amino-,hydroxyl,and carboxyl groups were the major fractions of MBF7,and the molecule weight was about 3.0×105 Da.In addition,the carbon and nitrogen sources favorable for the bioflocculant production were glucose and yeast extract respectively.When the initial pH of the medium was adjusted to 5.0,high flocculant efficiency could be achieved.Conclusion The bioflocculant MBF7 is a new macromolecule with high flocculating efficiency for Kaolin suspension,and could be produced under appropriate culture conditions.
Sensitivity of Different Cytotoxic Responses of Vero Cells Exposed to Organic Chemical Pollutants and their Reliability in the Bio-toxicity Test of Trace Chemical Pollutants
2010, 23(3): 219-229.
Objective To find a sensitive cytotoxic response to reflect the bio-toxicity of trace organic pollutants,the sensitivity and reliability of morphological change and proliferation inhibition of Veto cells exposed to 2,4,6-trichlorophenol(TCP)and the leachate from products related to drinking water(PRDW)were compared,and the mechanism of the morphological change in Vero cells exposed to chemical pollutants was studied.Methods Veto cells were treated by different concentration of TCP and the leachate from PRDW.Methylthiazol-2-yl-2,5-diphenyl tetrazolium bromide(MTT)assay was carried out for proliferation inhibition.Bioluminescence method was carried out as another method to test the toxicity of TCP.Flow Cytometry assay was used to test cell Apoptosis and damage of cell-membrane.Results 0.25mg/L TCP had an effect on cell morphology,and the proportion of morphologically changed cells increased with increasing TCP concentration.At low TCP concentrations,inhibition of cell proliferation did not seem to correlate to TCP concentration,and was negative when TCP concentration was<1.0mg/L.After exposure to leachate from PRDW extracted at different temperatures,the percentage of morphologically changed cells increased with extracting temperature,but the inhibition of cell proliferation failed to reflect the correlation between extracting temperature and proliferation inhibition of Vero cells.Although the Sensitivity of bioluminescence method seems to be similar to morphological change in Vero cells,the bacterial in this method is not homologous enough with human body cells to reflect the toxicity to human body.These imply cell morphological change is a more sensitive and reliable method to reflect bio-toxicity of organic pollutants than proliferation inhibition.Flow cytometry analysis and cell rejuvenation experiments indicated cell membrane damage,which results in cell morphological change,was an early and sensitive cytotoxic response comparing with necrosis.Conclusion These results indicated that the cell membrane toxicity represented by morphological changes is a more sensitive and reliable method to indicate the composite bio-toxicity of trace chemicals than proliferation inhibition,inhibition on bioluminescence and necrosis.Nevertheless,the quantification of morphological change should be studied further.
Exposure to Environmental Hexachlorocyclohexane (HCH) and Dichlorodiphenyltrichloroethane (DDT) among Rural Children in North Eastern China
2010, 23(3): 230-233.
Objective To assess HCH and DDT exposure levels and associated risk factors among 262 children aged 6-10 years in a northeastern rural area of China between April and May of 2008. Methods Eight HCH and DDT metabolites in serum samples were monitored by gas chromatography. A questionnaire was administered to identify the sources of pesticides in children' serum samples. Results At least one pesticide metabolite was detected in 81.7% of the tested children. Higher amounts of pp'DDD were detected in 50% of them. Children's age and their father's occupation as farmers, together with not changing work clothes after work, were the main risk factors for HCH and DDT exposure among them. Conclusion Children living in rural areas are experiencing multiple sources of organochlorine pesticide exposure. These pesticides may have been retained in the environment for a long period of time.
2010, 23(3): 234-243.
Objective Solar ultraviolet (UV) radiation is an important environmental factor that affects human health. The understanding of diurnal variations of UV radiation at anatomical sites may be helpful in developing ways to protect humans from the harmful effects of UV radiation. Methods In order to characterize the diurnal variations, the UV exposure values were measured at 30 min intervals by using Solar-UV Sensors and a rotating manikin in Shenyang city of China (41°51'N,123°27'E). Measurement data for four representative days (in each of the four seasons respectively) were analyzed. Results The diurnal variations in solar UV radiation at the shoulder, the forehead and the chest were similar to those associated with a horizontal control measurement. However, the diurnal variations at the eye and the cheek exhibited bimodal distributions with two peaks in spring, summer and autumn, and a unimodal distribution in winter. The UV exposure peaks at the eye and the cheek were measured at solar elevation angles (SEA) of about 30° and 40°, respectively. Conclusion The protection of some anatomical sites such as the eye from high UV exposure should not be focused solely on the periods before and after noon, especially in the places and seasons with high SEA.
2010, 23(3): 244-249.
Objective Low-intensity pulsed ultrasound (LIPUS) has been reported to enhance proliferation and to alter protein production in various kinds of cells. In the present study, we measured the neurites length after LIPUS treatment to define the effectiveness of LIPUS stimulation on neurons, and then we examined the acticity of GSK-3β to study the intracellular mechanism of neurite's outgrowth. Methods LIPUS was applied to cultured primary rat cortical neurons for 5 minutes every day with spatial- and temporal average intensities (SATA) of 10 mW/cm2, a pulse width of 200 microseconds, a repetition rate of 1.5 KHz, and an operation frequency of 1 MHz. Neurons were photographed on the third day after LIPUS treatment and harvested at third, seventh, and tenth days for immunoblot and semi-quantitative RT-PCR analysis. Results Morphology change showed that neurite extension was enhanced by LIPUS. There was also a remarkable decrease of proteins, including p-Akt, p-GSK-3β, and p-CRMP-2, observed on the seventh and tenth days, and of GSK-3β mRNA expression, observed on the seventh day, in neurons treated with LIPUS. Conclusion LIPUS can enhance elongation of neurites and it is possible through the decreased expression of GSK-3β.