ABSTRACT
Objective To study the distribution of ameloblastin(AMBN) gene polymorphism in coal-fire caused fluorosis (CFCF) in Chongqing municipality and the relationship between AMBN gene polymorphism and the susceptibility to dental fluorosis.Methods Under a case-control study,100 children aged 8-12 and 30 adults with dental fluorosis were enrolled in Wushan and Fengjie counties of Chongqing from December 2010 to February 2011.Another 100 children aged 8-12 and 30 adults with non-dental fluorosis were chosen as internal control groups together with 50 childrenand 30 adults without dental fluorosis were selected as external control groups in the non-epidemic area of Yubei district.DNA was extracted from peripheral blood sample of these people.Genotype of AMBN gene 7 extron 538_540delGGA,10 extron 657A＞G and 13 extron 986C＞T loci were detected using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)technique.Results The rates of 7 extron 538_540delGGA loci among case,internal and external control groups were as follows:GGA/GGA-/-61.2％ (74/121),78.5％ (102/130),74.3％ (52/70) ;GGA/-:24.0％ (29/121),15.4％ (20/130),22.9％ (16/70) ;-/-:14.8％ (18/121),6.1％ (8/130),2.8％ (2/70),the difference was statistically significant (x2=14.353,P＜0.05).The AA appeared to be 86.8％(105/121),93.1％(121/130),91.4％(64/70) and AG were 13.2％(16/121),6.9％(9/130),8.6％ (6/70),with difference not statistically significant (x2=2.972,P＞0.05).CC appeared as 81.0％ (98/121),90.0％(117/130),87.1％(61/70) while CT as 19.0％(23/121),10.0％(13/130),12.9％(9/70),with difference not statistically significant (x2=4.319,P＞0.05).In comparing with the two control groups,the frequency of GGA/GGA was decreasing (x2 values were 8.957,3.405,respectively,P＜0.05) while the frequency of-/-was increasing (x2 values were 5.134,6.833,respectively,P＜0.05).Results from the univariate analysis showed that the individuals who were carrying-/-genotype had an increased risk of suffering from fluorosis (OR values were 2.7,5.9,respectively,P＜0.05).When compared with the internal control group,the CT genotype of case group showed an increase (x2=4.139,P＜0.05) while individuals that carrying CT genotype had an increased risk of suffering from fluorosis (OR=2.1,P＜0.05),in epidemic-area.Conclusion Our results showed that the 7 extron 538_540delGGA and the 13 extron 986C＞T loci polymorphism in AMBN gene might serve as the susceptibility factors causing the coal-fired fluorosis.
ABSTRACT
Objective To understand the distribution of chemical elements in soil.To investigate the differences between patients under different state of fluorosis and normal population after preventive measurement was implemented to get rid of some chemical elements and to lower the urine fluoride levels so as to illustrate the pathogenesis of the disease.Methods Both ecological and comparative studies had been used to analyze the rates and levels of chemical elements.Teeth and skeletal from the patients with fluorosis and controls were taken and florin ion-selective-electrode method was used to determine urine the content of fluorine.Atomic Absorption Spectrometry was used to determine the copper,zinc,calcium,magnesium and iron contents in the whole blood.Differences of contents were analyzed.Results In Wushan county,the soil contents of nickel (r＝0.553,P＝0.050),iodine (r＝0.571,P＝0.041),fluorine (r＝0.303,P＝0.005),pH value (r＝0.304,P＝0.005) and the rates of fluorosis showed weaker positive relationship.In Fengjie county,the soil contents of mercury (r＝0.285,P＝0.001),nickel (r＝0.212,P＝0.00) and the rates of fluorosis also showed weaker positive relationship.In Wushan county,the urine fluoride level in the patients group [(0.64 ± 0.34) mg/L] was higher than that in the control group [(0.44 ± 0.59) mg/L],(P ＜ 0.05).In Fengjie county,copper [(29.63 ± 3.32)μmol/L] and urine fluoride [(0.83 ±0.37)mg/L] levels in the patients group showed higher than that in the control group [(26.76 ± 3.63) μmol/L,(0.53±0.23)mg/L],(P＜0.05).zinc (Zn) [(76.13 ± 11.24)μmol/L],calcium (Ca) [(1.87± 0.25)mmol/L],magnesium (Mg)[(1.41 ±0.18)mmol/L] and fluoride [(0.83 ±0.37)mg/L] levels in urine of the patients in children were higher in Fengjie than that in Wushan [(71.95 ± 7.53) μmol/L,(1.43 ±1.34) mmol/L,(1.34±0.15) mmol/L,(0.64 ±0.34)mg/L],(P＜0.05).Mg [(1.56± 1.96)mmol/L],ferrum [(8.15 ± 1.00)mmol/L] and fluoride [(2.17 ± 0.99)mg/L] levels among adult patients were significantly higher than in the control group [(1.46±0.16) mmol/L,(7.64± 1.00)mmol/L,(1.44±1.22)mg/L] (P＜0.05).Conclusion Soil,rich in alkaline and fluorosis could increase the intake of fluorine while nickel,cadmium,iodine content in soil might relate to the occurrence of fluorosis.Residents living in endemic areas where anti-fluorine elements as Zn,Ca and Mg were in shortage,might be affected by these chemical elements that related with fluorosis.
ABSTRACT
ObjectiveTo investigate the differences of whole blood chemical elements and urinary fluorine between patients with endemic fluomsis and patients without endemic fluorosis,and to find out the elements associated with endemic fluorosis and further lay a theoretical basis for clarify the pathogenesis of the disease.MethodsUsing case-control study,100 children aged 8 - 12 with dental fluorosis in Wushan and Fengjie counties of Chongqing from December 2010 to February 2011,and 30 adults with skeletal fluorosis were enrolled as case group; 100 children aged 8 - 12 without dental fluorosis and 30 adults without skeletal fluorosis were enrolled as internal control group; and 50 children without dental fluorosis and 30 healthy adults were selected as external control group in non-epidemic areas in Yubei district.Whole blood copper,zinc,calcium,magnesium,iron and urinary fluorine of all subjects were determined,and differences of these indexes were compared between groups.ResultsThe levels of copper,zinc,calcium,magnesium,iron and urinary fluorine of children in the case group were (30.08 ± 2.83),(74.04 ± 9.75)μmol/L,(1.65 ± 0.29),(1.37 ± 0.17),(6.79 ± 1.27)mmol/L,and (0.73 ±0.37)mg/L,respectively; the levels of these elements of children in internal control group were (28.65 ± 3.96),(72.83 ± 11.35)μmol/L,(1.62 ± 0.27),(1.36 ± 0.18),(6.73 ± 1.22)mmol/L,and (0.48 ± 0.21)mg/L,respectively; in external control group were (32.03 ± 2.99),(77.78 ± 10.85)μmol/L,(1.41 ± 0.11),(1.43 ± 0.13),(7.66 ±0.55)mmol/L,and (0.49 ± 0.26)mg/L,respectively(all P＜ 0.05),the comparison between any two groups indicated the levels of copper,zinc,magnesium,iron of the case group were lower than that of external control group,urinary fluorine was higher than that of internal and external control groups(all P ＜ 0.05).The levels of copper,zinc,calcium,magnesium,iron and urinary fluorine of adult case were (26.93 ± 4.37),(95.89 ± 12.45)μmol/L,(1.50 ± 1.76),(1.56 ± 1.96),(8.15 ± 1.00)mmol/L,and (2.17 ± 0.99)mg/L; internal control group were (26.26 ±4.96),(94.86 ± 12.18)μmol/L,(1.57 ± 0.12),(1.46 ± 0.16),(7.64 ± 1.00)mmol/L,and (1.44 ± 1.22)mg/L;external control group were (26.20 ± 2.96),(96.52 ± 11.11)μmol/L,(1.48 ± 0.14),(1.45 ± 0.16),(7.81 ±0.91 )mmol/L,and (0.55 ± 0.21 )mg/L,respectively.The levels of magnesium,iron and urinary fluorine of case group were higher than that of internal control group,magnesium and urinary fluorine were higher than that of external control group(all P ＜ 0.05).ConclusionsIn vivo anti-fluorine elements are deficient in the areas with endemic fluorosis.Other chemical elements,the environment and genetic factors may be related to the pathogenesisof the disease,which needs a further comprehensive analysis.