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Objective To investigate the combined effects of fluoride and aluminum intoxication on bones and their possible mechanisms.Methods Kunming mice were divided into nine groups according to the factorial experiment design.Different dose of fluoride(NaF,0,50,150 mg/L)and/or aluminum(AlCl3,0,200,600 mg/L)was administered to each group in drinking water.After 24 weeks,the degree of mottled teeth and the histomorphometric parameters,such as the bone trabecula and osteoid areas,the number of osteoblasts and osteoclasts,and pathologic changes in femur were observed.Results Aluminum could also caused mottled teeth(in degree 4).The mottled teeth in the combined groups were more serious than those in fluoride or aluminum alone group.The interaction between fluoride and aluminum existed in the changes of bone trabecula and osteoid areas(F=2.963,3.688,P＜0.05),and not existed in changes of the number of osteoblasts and osteoclasts(F=2.347,0.888,P＞0.05).In high fluoride group,the trabecula and osteoid areas were(50 675.47±22 916.34),(10 733.97 ±3015.55)μm2,but it increased to(75 988.64±13 797.21),(16 402.88±4605.83)μm2 when combined with high aluminum(P＜0.05),and the group of high fluoride +low aluminum increased to(69 277.16±19 837.51),(18 564.79±6362.47)μm2 (P＜0.05),so aluminum antagonized the effects induced by fluoride;the area of bone trabecula of group of high aluminum was(60 718.43 ±17 574.37)μm2,but it increased[(75 988.64±13 797.21),(82 474.94±15 466.66)μm2]when combined with high or low fluoride(P＜0.05),and the combined effects showed a similarity to those in high aluminum group.The prominent osteoporosis with increased osteoid and cartilage tissues,and decreased amount of bony matrix and minerals were the main histopathological changes in the bone.Conclusions Both high aluminum and fluoride intoxication can result in mottled teeth,their combined effects are more serious than the individual effect.The prominent injury of combined fluoride and aluminum intoxication is osteomalacia and osteoporosis.
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Objective To explore the interaction characters of fluoride and aluminum by analyzing the changes of bone metabolism in mice. Methods Kunming mice were randomly divided into nine groups according to the factorial experiment, design of two factors and three levels. The animals in different groups were fed with various doses of fluoride(NaF, 0,50,150 mg/L) and/or aluminum(AlCl3, 0,200,600 mg/L) in drinking water for 24 weeks. Serum calcium, phosphor, magnesium, alkaline phosphatase, osteoealine, parathyroid, and urinary calcium and phosphor were tested. Results We found interaetians of fluoride and aluminum with serum calcium, osteoealine and urine calcium(F=17.370,4.399,9.448, P<0.01), but not with serum phosphor, magnesium, alkaline phosphatase, parathyroid or urinary phospbor(F=0.416,0.415,1.921,1.362, 1.630, P 0.05). The serum levels of calcium and osteoealine in high fluoride group were (1.13±0.27)mmol/L and (6.56±5.74)μg/L, respectively, which were lower than in the control group[ (1.82±0.37)mmol/L and (23.45±15.40)laeJL, respectively], but the levels were elevated to (1.76±0.36)mmol/L and (10.57±4.28)μg/L when high fluoride was combined with low aluminum, and further elevated to (2.10±0.51)mmol/L and (15.73±3.15)μg/L when high fluoride was combined with high aluminum. The urinary calcium level in low fluoride group [ (6.24±2.61)retool/retool Cr] was higher than that in the control group[ (3.12±2.04)retool/retool Cr], but it was decreased in low fluoride and aluminum groups[ (0.81±0.44), (1.23± 0.41)mmol/mmoi Cr, respectively]. On the other hand, the levels of serum ealeium and osteocaline in high aluminum group were (1.07±0.68)mmol/L and (7.21±5.22)μg/L, elevated to (1.47±0.18)mmol/L and (10.98±4.35) μg/L when low fluoride was combined wth high aluminum, and further elevated to (2.10±0.51)mmol/L and (15.73± 3.15)μg/L when high fluoride was.combined with high aluminum, respectively, and the combined effects showed the same trend of higher aluminum. Conclusions Aluminum antagonized fluoride-induced effects, whereas fluoride aggravated the effects caused by aluminum in this experimental conditions. The biomarkers of bone formation and mineralization were suppressed in the combined groups, so the combined effects could interfere with the course of bone turnover by inhabiting bone formation and mineralization, leading to the disorder of bone metabolism eventually.
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To explore the role and application of Meta-regression and subgroup analyses to recognize and control the heterogeneity in Meta-analysis, Meta-regression models were established by secondary data to screen the factors resulting heterogeneity,and subgroup analyses were used to compare the change of heterogeneity before and after.The heterogeneity was found in the Meta-analysis(Q=44.71,df=27,P=0.017).Sample size and region were selected(P=0.012 and P=0.091,respectively)by Meta-regression from many possible factors such as sample size,year,region and case/contml ratio.The Q values were lowered from 44.71 to 32.11 after subgroup analyses.Thus,Metaregression method was convenient and reliable to screen the affected factors of heterogeneity,and subgroup analyses based on the hypothesis that could significantly lower the heterogeneity.It was recommended to a combined use when an obvious heterogeneity existed but was in need to get an overall result in Metaanalysis.We could correctly judge and lower the heterogeneity to increase the robustness and rationality of results from Meta-analysis.
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<p><b>OBJECTIVE</b>To explore the effects of cadmium on zinc metabolism and its function and the protective effects of pre-supplement zinc to it.</p><p><b>METHODS</b>NS or different doses of CdCl(2) were injected to pregnant dams intraperitoneally at the 7th, 10th and 13th day of gestation respectively. At the 21st pregnant day embryos were taken out from the pregnant rats. Another rats of pre-supplement zinc or no pre-supplement zinc group were injected different doses of CdCl(2) or NS intraperitoneally after 6 days. After 24 hours the rats were killed. The contents of Cd, Zn and relative biomarkers of effect of liver, brain or serum were detected in both embryos and adult rats.</p><p><b>RESULTS</b>Compared with control group, the contents of T-AOC and Ach were significantly reduced in the Cd treatment group in the embryonic brains, the activity of AKP in the embryonic liver tissues was decreased, and The Cd content was increased significantly in embryonic liver and was negatively correlated with the Zinc content in the embryonic brain. There were no differences in the activities of SOD and AKP and the contents of Cd and MDA between pre-supplement Zn control group and no supplement Zn control group, but higher content of Zn in liver and serum in the former. Compared with no supplement Zn control group, there were higher contents of Cd in liver and serum, Zn and MDA in liver, lower activities of SOD in liver and AKP in liver and serum, and lower content of Zn in serum in the Cd treatment groups. Pre-supplement Zn significantly increase the content of Zn and the activities of SOD in liver and AKP in serum, decrease the content of MDA in liver and Cd in serum resulted by Cd treatment only. The content of Zn and the activity of AKP in serum and the activities of SOD and AKP in liver were negatively correlated with the content of Cd in corresponding tissue significantly.</p><p><b>CONCLUSION</b>Cadmium can enter embryo and enter brain by permeating the brain-blood barrier during the embryonic period. The decrease of AKP activity, some neural transmitter and capacity of anti-lipid peroxidation that are related with Zn in embryos are caused when the pregnant rats are administered with cadmium. Cd can inhibits the activities of AKP and SOD in liver, and the activity of AKP in serum respectively, and increase the content of MDA in liver dose-dependently. The effects induced by cadmium are related with zinc abnormal distribution. Pre-supplement zinc to rats can antagonize these effects in different degree.</p>
Subject(s)
Animals , Female , Male , Pregnancy , Rats , Cadmium , Toxicity , Liver , Metabolism , Maternal Exposure , Metallothionein , Metabolism , Rats, Sprague-Dawley , Zinc , Metabolism , PharmacologyABSTRACT
<p><b>OBJECTIVE</b>To develop a rapid and definite diagnostic test of bacterial enteritis caused by pathogenic enterobacteria, the most frequent etiologic agent of infectious enteritis in the world.</p><p><b>METHODS</b>A set of conventional PCR assays were applied to detect and identify salmonella, shigella, and E. coli O157:H7 directly from pure culture and fecal samples. The general primers of pathogenic enterobacteria were located on the uidA gene, which were found not only in E. coli nuclear acid, but also in shigella and salmonella genes. Shigella primer was from ipaH gene whose coded invasive plasmid relative antigen existed both in plasmid and in genome. The primers of salmonella were designed from the 16SrRNA sequence. The primer of E. coli O157:H7 was taken from eaeA gene. Five random primers were selected for RAPD. The detection system included common PCR, semi-nested PCR and RAPD.</p><p><b>RESULTS</b>This method was more sensitive, specific and efficient and its processing was rapid and simple. For example, the method could be used to specifically detect and identify salmonella, shigella, and E. coli O157:H7, and its sensitivity ranged from 3 to 50 CFU, and its detection time was 4 hours.</p><p><b>CONCLUSION</b>This PCR method, therefore, can serve as a routine and practical protocol for detecting and identifying pathogenic microorganisms from clinical samples.</p>