Progress in the effect of fluorosis on skeletal muscle and its related molecular mechanisms / 中华地方病学杂志

Fluoride has dual health effects. Proper amount of fluoride plays an important role in bone development, prevention of dental caries and nervous system activity. Excessive fluoride causes chronic systemic diseases with dental fluorosis and skeletal fluorosis as the main symptoms. Fluorosis causes morphological and structural changes and function damage in skeletal muscle. Low concentration of fluoride induces muscle canal hypertrophy in skeletal muscle, while high concentration of fluoride leads to skeletal muscle atrophy by causing a series of signal pathway abnormalities. Abnormal changes in phosphatidylinositol-3-hydroxykinase/protein kinase B (PI3K/Akt) signal pathway, oxidative stress, and ubiquitin-proteasome pathway all play important roles in skeletal muscle injury caused by fluorosis. In this paper, the effect of fluoride on skeletal muscle and its related molecular mechanisms are reviewed.

Effects of fluoride on longitudinal growth and pathological changes of cultured rat metatarsal bones / 中华地方病学杂志

Objective To study the effects of fluoride on longitudinal growth and pathological changes of cultured rat metatarsal bone rudiments.Methods Twenty-four neonatal SD rats were divided into four groups according to the random number table,then the second,third and fourth metatarsal bone rudiments were surgically isolated.The left metatarsal bone rudiments were cultured in α-MEM without F-as control group and the right metatarsal bone rudiments from the same rat were cultured in α-MEM with 1 × 10-7,1 × 10-6,1 × 10-5 and 1 × 10-4 mol/L F-.The length and width of the mineralized area of metatarsal were measured on day 0,day 1,day 4 and day 7,respectively,and the pathological changes of metatarsal bone rudiments were observed by the routinely paraffin-embedded sections method on day 7.Results On day 7,the length of the mineralized area was significantly lower of right metatarsal bone [(240.5 ± 139.3)μm] than the left metatarsal bone [(394.1 ± 173.9)μm,t =4.37,P ＜ 0.01] in the 1 × 10-4 mol/L F-group,but the width of the mineralized area [(239.9 ± 119.4)μm] was not different significantly compared to the left metatarsal bone [(223.3 ± 99.9)μm,t =0.44,P ＞ 0.05].The relative vertical growth rate of the mineralized area on day 4 was significantly lower of right metatarsal bone [(2.43 ± 1.44)％] than left metatarsal bone [(8.34 ± 1.74)％,t =3.21,P ＜ 0.01] in 1 × 10-4 mol/L F-group,and the difference was also significant on day 7 [(16.16 ± 2.87)％ vs.(26.52 ± 4.46)％,t =3.13,P ＜ 0.01].Toluidine blue staining results showed that the thickness of cartilage cells of proliferation and hypertrophic layers was significantly lower of right metatarsal bone [(111.33 ± 27.29),(125.33 ± 30.08)μm] than left metatarsal bone [(127.33 ± 38.36),(160.50 ± 42.73)μm,t =4.82,5.81,all P ＜ 0.01] in 1 × 104 mol/L F-group.The ratio of proliferative and hypertrophic layers was significantly higher of right metatarsal bone (0.93 ± 0.36) than left metatarsal bone (0.83 ± 0.32,t =4.42,P ＜ 0.01) in 1 × 10-4 mol/L F-group.Conclusions Our findings indicate that excessive fluoride could cause longitudinal bone growth inhibition.Such growth inhibition is mediated by decreased chondrocyte proliferation and differentiation and the disproportion of proliferation and differentiation.

Efficiency Analysis of Humanism in Nursing Management of Patients with Spinal Cord Injury / 中国医学伦理学

Objective:To explore the effectiveness of humanism concept in the management of patients with spi-nal cord injury care.Methods:Choose between January 2011 and February 2011 hospitalized in our hospital 112 cases of spinal cord injury patients, randomly divided into control group and observation group ( 56 cases) , com-pared two groups of nursing effect.Control group routine nursing management, observation group will humanistic nursing management idea runs through in the routine nursing management.Results:Aware of knowledge about health education group is significantly higher than the control group, patients satisfaction survey in nursing, be-tween the two groups statistically significant depression levels lower than the control group.Conclusions:In the nursing management of patients with spinal cord injury in the application of humanistic nursing concept effect is good, not only improve the effect of the nursing, and obviously improve the patient′s satisfaction, promote the pa-tient′s psychological adaptability.

The effect of different fluoride concentrations on the expression of transforming growth factor-beta1 in ameloblast of rat incisor / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of different concentrations of fluoride on the expression of transforming growth factor-beta1 (TGF-beta1), and explore the mechanism of dental fluorosis.</p><p><b>METHODS</b>40 Wistar rats were randomly divided into three groups, and supplied with low dose F(-)(60 mgxL(-1), 13 rats), high dose F(-)(120 mgxL(-1), 13 rats) and distilled water(control group, 14 rats) respectively. After 10 weeks, hematoxylin-eosin (HE) and immunohistochemistry staining were used to observe the changes of the ameloblasts and the expression of TGF-beta1 in rat incisors.</p><p><b>RESULTS</b>The fluoride groups showed typical symptoms of dental fluorosis. The surfaces of the rat teeth fed with fluoride appeared chalky color and cross striation on the enamel surface. The HE staining showed that the morphous of ameloblast were disarranged and cellular derangement, even appeared vacuolar change. TGF-beta1 were expressed both in ameloblast of the secretory and maturation stage, and also in stellate reticulum and stratum intermedium. The expression of TGF-beta1 in rat's ameloblasts in experiment group was significantly lower than that in the control group (P<0.01), yet low dose group and high dose group still had no significant difference (P>0.05).</p><p><b>CONCLUSION</b>By inhibiting the expression of TGF-beta1 in ameloblast, fluoride interferes the normal signal transduction between epithelial and mesenchymal, and affect the differentiation and development of enamel, so leading to the occurrence of dental fluorosis.</p>

Second trimester prenatal screening for Down's syndrome in Mainland Chinese subjects using double-marker analysis of α-fetoprotein and β-human chorionic gonadotropin combined with measurement of nuchal fold thickness

<p><b>INTRODUCTION</b>This study examines the effectiveness of double-marker analysis for α-fetoprotein (AFP) and β-human chorionic gonadotropin (β-hCG) combined with measurement of nuchal fold thickness (NT) in the detection of Down's syndrome (DS) in Mainland Chinese subjects during second trimester prenatal screening.</p><p><b>MATERIALS AND METHODS</b>We examined pregnant women with a singleton pregnancy between 15 and 21 weeks of gestation who underwent second trimester screening for DS using double-marker analysis for AFP and β-hCG combined with ultrasound measurement of NT. The combined risk of DS was calculated. A cut-off of 1/270 was used to define a pregnancy at high-risk of DS. Amniocentesis was offered to all patients with high-risk pregnancies.</p><p><b>RESULTS</b>Using double-marker analysis for AFP and β-hCG in combination with measurement of NT, the detection rate of DS increased from 66.7% to 77.8% when compared with double-marker analysis alone with similar false-positive rates (4.35%, 4.83% respectively). Using receiver operating characteristic curve (ROC) analysis, we determined that the double-marker analysis combined with measurement of NT exhibited an increased area under the curve (AUC) of 0.835 (95% CI: 0.743 to 0.927) when compared to double-marker analysis alone, which had an AUC of 0.748 (95% CI: 0.635 to 0.860). In addition, both methods were more effective than any other single test such as AFP, free β-hCG or NT measurement.</p><p><b>CONCLUSION</b>Second trimester prenatal screening using double-marker analysis for AFP and β-hCG combined with measurement of NT is effective for the detection of DS in Mainland Chinese pregnancies.</p>

Effects of Fluoride and Aluminum Alone and in Combination Exposure on Proliferation and Cell Cycle of MC3T3-E1 Cells / 环境与健康杂志

Objective To explore the effects of different concentrations of fluoride, aluminum alone and in combination exposure on mice parietal bone cell subclone 14 (MC3T3-E subclone 14), and to elucidate the pathogenesis of endemic fluorosis. Methods The proliferation of MC3T3-E1 cells exposed to 10-9 -10-3 mol/L NaF alone, 50 ?mol/L NaF and 5 ?mol/L AlCl3 alone and in combination ,was measured by CCK-8, and the change of cell cycle was measured by flow cytometry after treatment with various concentrations of fluoride and aluminum. Results Fluoride alone did not promote osteoblast MC3T3-E1cells proliferation, higher concentration fluoride inhibited MC3T3-E1 cells proliferation. Fluoride and aluminum combined exposure (50 ?mol/L NaF +5 ?mol/L AlCl3) stimulated proliferation of MC3T3-E1 cells (P

Primary Culture of Osteoblasts of Neonatal Mice:a Comparative Research / 环境与健康杂志

Objective To confirm an alternative method for primary culture of osteoblasts through comparison of two primary culture methods. Methods Calvarias were dissected from newborn Kunming mice, osteoblasts were isolated with serum-containing collagenase digestion method and sequential digestion method respectively. The osteoblasts were observed under invert microscope, the growth curve was made with the application of MTT method, the rate of living osteoblasts was counted with trypan blue method respectively. Results Compared with the serum-containing collagenase digestion method, the sequential digestion method presented higher production of osteoblasts, higher cell survival rate (P

Study on the difference in DNA damage of human lymphocyte caused by arsenicals / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore whether there is difference in arsenicals-induced DNA damage of human lymphocyte.</p><p><b>METHODS</b>Lymphocyte were sterilely collected from healthy donor and exposed to sodium arsenite (AsIII), sodium arsenate(AsV) and methyl sodium arsenate(MAsv) at 1,5,10,20 and 50 mumol/L. After incubation of 24 hours, cells were collected by centrifugation and DNA damage was detected by single cell gel electrophoresis (SCGE).</p><p><b>RESULTS</b>The comet frequency distribution of all groups except 1 mumol/L group of MAsV were significantly different from that of control. The comet length of all groups except 1 mumol/L group of AsV and 1.5 mumol/L groups of MAsV were significantly higher than that of control. There were correlations between the doses of arsenicals and the ratios of comet cell or length of comet(rAsIII = 0.8134, rAsV = 0.8734, rMAsV = 0.8994).</p><p><b>CONCLUSION</b>DNA damage in human lymphocyte were induced by all the three arsenicals. A dose-effect relationship was observed between exposure doses of the same arsenical and DNA damage. With different arsenicals but the same exposure dose, the DNA damage level was as follow: AsIII > AsV > MAsV.</p>