Measurement of Key Elements in Rare Earth Alloy by Pulsed Glow Discharge Mass Spectrometry / 分析化学

Pulsed glow discharge mass spectrometric(Pulsed-GDMS) method for the measurement of 7 kinds of key elements(Mg,Fe,Cu,La,Ce,Pr and Nd) in rare earth alloys was established. The influence factors of measurement repeatability, such as pulse time, sample homogeneity, anode cap, flow tube, corn, and sample tablet density were systematically studied. The results showed that,for elements with mass fraction of more than mg/g, the parts (anode cap, flow tube and corn) had the largest influence on measurement repeatability. When the new graphitic parts were used and no parts were changed during the whole measurement,the relative standard deviation (RSD) was less than 3%. However, the RSD were 2%-11%and 3%-21% when the new graphitic parts and the reusable parts were used and changed,respectively. The second influence factor of measurement repeatability was the tablet density. The results showed that,the lower the density,the worse the measurement repeatability, and for the dense tablet, the RSD was less than 3%. Key elements in 1# rare earth alloy were measured by high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS), and the analytical results were used as reference values for the calibration of Pulsed-GDMS. The relative sensitivity factors (RSF) were obtained, and the key elements in 2# rare earth alloy were measured by Pulsed-GDMS after calibration. The analytical results of key elements in 2#sample by Pulsed-GDMS and HR-ICP-MS were compared, and the results showed that for the dense sample, the analytical results showed good agreement. Under the optimal conditions, the expanded uncertainty of measurement by Pulsed-GDMS reduced to 3%-10%.

Expression of integrin α5 and β1 in osteoblast in the process of gingipains-induced apoptosis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the regulatory mechanisms of integrin α5 and β1 in osteoblast in the process of gingipains-induced apoptosis.</p><p><b>METHODS</b>Gingipains were isolated and purified from supernatants of Porphyromonas gingivalis W83 which was cultured under standard anaerobic conditions. MC3T3-E1 was challenged with or without 8.3480 U/L gingipains for 48 h and apoptosis was examined by transferase-mediated deoxyuridine triphosphate-biotin nick end labeling-(4-Amidinophenyl)-6-indolecarbamidine dihydrochloride (TUNEL-DAPI) staining. The expression of integrin α5 and β1 was analyzed by Western blotting after MC3T3-E1 was treated under different conditions.</p><p><b>RESULTS</b>Arginine-specific proteinases(Rgp) activity was (41.74 ± 2.11) U/L and lysine-specific proteinase(Kgp) was (1.02 ± 0.25) U/L.Gingipains induced MC3T3-E1 cells apoptosis after 48 h. Compared with control group, expression of integrin α5 and β1 was down-regulated by gingipains in a time-dependent manner within short periods ( ≤ 72 h), integrin α5 and β1 relative expression was (0.485 ± 0.039),(0.504 ± 0.002) at 48 h,(0.398 ± 0.058),(0.179 ± 0.001) at 72 h respectively (P < 0.05). After 72 h, integrin α5 expression in MC3T3-E1 cells was stable compared with control group while integrin β1 was still lower(control group:1.000 ± 0.000, 96 h:0.604 ± 0.003, 120 h: 0.357 ± 0.002) (P < 0.05). Proteinase inhibitor tosyl- L- lysine-chloromethyl-ketone(TLCK) effectively blocked the activity of gingipain and inhibited down-regulation of integrin α5 and β1 induced by gingipains from (0.398 ± 0.058,0.179 ± 0.001 ) to (0.781 ± 0.012, 0.857 ± 0.060) (P < 0.05). TLCK alone did not have any effect on integrin α5 and β1(P > 0.05). Gingipains also decreased integrin α5 and β1 in a dose-dependent manner.When cells were treated with 20.8700 U/L gingipains, integrin α5 and β1 relative expression reached to the lowest(0.105 ± 0.004,0.020 ± 0.000) (P < 0.05).</p><p><b>CONCLUSIONS</b>Gingipains inhibited the expression of integrin α5 and β1 in a time- and dose- dependent manner in osteoblasts in the process of apoptosis, which may not be mediated by direct proteolytic effect.</p>

Effect of sonicated extracts of Porphyromonas gingivalis on osteogenic differentiation of mouse osteoblasts / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of sonicated extracts of Porphyromonas gingivalis (Pg) on osteogenic differentiation of mouse osteoblast cell line MC3T3-E1.</p><p><b>METHODS</b>PgW83 was cultured under standard anaerobic conditions and extracted by sonication. Mouse osteoblast cell line MC3T3-E1 was cultured with various concentrations of the extraction (0, 10, 100, 1000 mg/L). Western blotting was applied to investigate the expression of osteocalcin (OC), bone sialoprotein (BSP), osteopontin (OPN) and osteonectin (ON). The activity of alkaline phosphatase (ALP) was detected by microplate reader after 14 days. Mineralization nodule formation was measured by alizarin red staining after 21 days.</p><p><b>RESULTS</b>Compared with the control group, the extracts of Pg decreased OC and ON expression in a dose-dependent manner (OC relative expression:1.000 ± 0.000,0.852 ± 0.110,0.625 ± 0.451,0.213 ± 0.053), (ON relative expression: 1.000 ± 0.000, 1.035 ± 0.133,0.141 ± 0.023,0.020 ± 0.003) (P < 0.05). The expression of OPN was down-regulated significantly in MC3T3-E1 treated with 1000 mg/L extraction (0.572 ± 0.162) compared with control group, 10 and 100 mg/L (1.000 ± 0.000, 1.029 ± 0.135, 1.199 ± 0.337) (P < 0.05). The expression of BSP remained unchanged when the cells were cultured with or without extraction (BSP relative expression:1.000 ± 0.000,0.831 ± 0.182,0.897 ± 0.115,0.778 ± 0.235) (P > 0.05). Meanwhile, the extracts of Pg decreased ALP activity [control group:(0.0275 ± 0.0014) U/gprot, 10 mg/L: (0.0140 ± 0.0011) U/gprot, 100 mg/L: (0.0057 ± 0.0013) U/gprot, 1000 mg/L: (0.0020 ± 0.0008) U/gprot] (P < 0.05) and reduced mineralization nodule formation.</p><p><b>CONCLUSIONS</b>The results suggest that Pg may inhibit osteoblasts'osteogenic function by down-regulation of osteogenic differentiation related proteins.</p>

Correlation between tag single nucleotide polymorphisms of microRNA regulatory genes and the genetic susceptibility of primary liver cancer / 中华预防医学杂志

<p><b>OBJECTIVE</b>This study aimed to understand the correlation between tag single nucleotide polymorphisms (tSNP) of microRNA regulatory genes and the gentic susceptibility of primary liver cancer.</p><p><b>METHODS</b>1:1 case-control study was applied in this research. A total of 532 primary liver cancer patients in 2 teaching hospitals in Zhengzhou city were enrolled as case group.532 healthy individuals were enrolled as control group. The subjects were surveyed by a face-to-face interview and 5 ml of peripheral venous blood were collected. Candidate tSNP were screened from DICER1, RAN and GEMIN4 gene, respectively. PCR-RFLP or Allele specific PCR was applied for genotyping of the subjects. Conditional logistic regression model and Multifactor-Dimensionality Reduction method were applied for analyzing the correlation between tSNP of above genes and gentic susceptibility of primary liver cancer. The gene-environment interaction was also analyzed.</p><p><b>RESULTS</b>The frequencies of genotype CC, CT, TT in rs14035 locus were 67.29% (358/532), 28.20% (150/532), 4.51% (24/532) in case group, and 70.30% (374/532), 28.20% (150/532), 1.50% (8/532) in control group, respectively (χ2=8.35, P<0.05). The frequencies of genotype GG, GA, AA in rs1045491 locus were 71.05% (378/532), 26.69% (142/532), 2.26% (12/532) in case group, and 80.45% (428/532), 18.42% (98/532), 1.13% (6/532) in control group, respectively (χ2=13.17, P<0.01); the frequencies of genetype GG, GT, TT in rs2291778 locus were 53.38% (284/532), 40.23% (214/532), 6.39% (34/532) in case group, and were 25.94% (138/532), 63.91% (340/532), 10.15% (54/532) in control group (χ2=83.71, P<0.01). TT genotype in rs14035 locus (OR=2.54, 95%CI: 1.19-6.32) and GA genetype in rs1045491 locus (OR=1.74, 95%CI: 1.08-2.66) were susceptible genotype of primary liver cancer, whereas GT (OR=0.52, 95%CI: 0.43-0.75) and TT genotype (OR=0.62, 95%CI: 0.46-0.86) in rs2291778 locus were protective genotype. Haplotype analysis showed that haplotype 3 (AACTGGGT) (OR=1.42, 95%CI: 1.10-1.82) and haplotype 5 (AGCCAGCC) increased the risk of occurrence of primary liver cancer (OR=1.36, 95%CI: 1.02-1.80), whereas haplotype 2 (AACTATCC) (OR=0.69, 95%CI: 0.52-0.91) and haplotype 6 (AACTGTGT)(OR=0.61, 95%CI: 0.45-0.81) decreased the risk. Subjects exposed to allele A of rs1045491, allele T of rs14035 and HBV infection intend to be the high risk population of primary liver cancer (OR = 3.72, 95%CI: 2.38 - 5.56).</p><p><b>CONCLUSION</b>Genotypes of TT in rs14035 locus, and GA in rs1045491 locus may be susceptible genotypes of liver cancer carcinogenesis. T allele in rs2291778 locus is a non-susceptible allele of primary liver cancer. Combined effects of multigene alleles and multi-locus genotype may have a synergistic role in the carcinogenesis of liver cancer.</p>

Population-based case-control family study on risk factors of esophageal cancer in high incidence area / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the risk factors of esophageal cancer (EC) in the high-incidence regions, so as to provide scientific evidence for taking effective prevention measures.</p><p><b>METHODS</b>A population based case-control family study was carried out. 1711 case family members in 505 families in which one of the couple or their first degree relatives suffered from EC were selected from high incidence in Henan province. Control families without neoplasm were selected from the same villages in matching conditions of age, sex, and family members. All information of case and control families was collected by Questionnaire of Life and Health of Inhabitant. The data were analyzed with logistic regression model.</p><p><b>RESULTS</b>Compared with the control families,it was shown that hobby for smoked food [2.10% (36/1711), 0.82% (14/1711); chi2 = 9.82, P = 0.00; OR = 2.61, 95% CI: 1.40 - 4.85], hobby for fried food [7.17% (66/921), 3.91% (35/894) ; chi2 = 9.13, P = 0.00; OR = 1.90, 95% CI: 1.24 -2.89], hobby for raw and hard food [13.36% (123/921), 8.95% (80/894); chi2 = 8.87, P =0.03; OR =1.57, 95% CI: 1.16 - 2.11], and hobby for hot food [20.05% (343/1711), 15.20% (260/1711); chi2 = 13.87, P= 0.00; OR= 1.40, 95% CI: 1.17 - 1.67], the history with mental stimulated [6.72% (115/1711), 3.10% (53/1711); chi2 = 24.06, P = 0.00; OR = 2.25, 95% CI: 1.62 -3.14], upper digestive symptom history [19.40% (332/1711), 12.74% (218/ 1711); chi2 = 28.15, P = 0.00; OR= 1.65, 95% CI: 1.37 - 1.99] entered the last model, and were responsible for the higher risk of EC. Eating fast was shown to be a protective factor [20.85% (192/921), 25.14% (225/895); chi2 = 4.73, P =0.03; OR = 0.78, 95% CI: 0.63 - 0.98].</p><p><b>CONCLUSION</b>EC is a kind of malignant tumor caused by multiple factors. Prevention and control of EC should be initiated from environmental factors, life style, genetic factors and social-psychological factors comprehensively.</p>

DNA repair gene xeroderma pigmentosum group D 751 polymorphism and the risk on esophageal cancer:a Meta-analysis / 中华流行病学杂志

Objective To explore the association between XPD codon 751 polymorphism and esophageal cancer (EC) by systematically reviewing the risk of the original studies. Methods A comprehensive search was conducted to identify all case-control studies of XPD codon 751 polymorphism and EC risk. Meta-analysis was applied with Rev Man 4.2 software for calculation of pooled OR value (with 95%C1)of EC, esophageal squamous cell carcinoma (ESCC)and esophageal adenocarcinoma (EAC). Results Of the 12 case-control studies selected for this Meta-analysis, a total of 2558 EC cases and 5122 controls were included. Compared with the wild-type homozygote Lys/Lys, the pooled Odds Ratios (with 95% CI) of Lys/Gln, Gin/Gin, (Lys/Gln + Gln/Gln) genotypes of XPD codon 751 polymorphism for EC risk were 1.19(1.05, 1.34), 1.22(0.86, 1.74), 1.20(1.01,1.42), respectively. In a stratified analysis, a total of 1417 ESCC cases and 2312 controls were included, and individuals carrying Lys/Gln genotype or (Lys/Gln+Gln/Gln) had 1.22-fold or 1.24-fold excess risks for ESCC compared with those carrying Lys/Lys genotype. A total of 935 EAC cases and 2604 controls were included, and none of the genotype of XPD codon 751 genetic polymorphism was found to be related to EAC. Conclusion Both heterogyzote Lys/Gln and (Lys/Gln + Gln/Gln) for XPD codon 751 genetic polymorphism were associated with an increased risk of developing esophageal cancer. Furthermore, heterogyzote Lys/Gln and (Lys/Gln + Gln/Gln) for XPD codon 751 genetic polymorphism might have increased the risk of ESCC, but have no association with EAC.

Expression of survivin and NF-kappaB in peripheral T-cell lymphoma and its significance / 中国实验血液学杂志

This study was aimed to explore the expression of survivin and NF-kappaB in the peripheral T-cell lymphoma and its significance. Immunohistochemistry method was used to detect the expressions of survivin and NF-kappaB in 26 cases of lymphosarcoma. 30 cases of benign reactive lymphohistiocytosis were selected as control tor analysis. The results showed that the expression of survivin in 21 patients with lymphoma was positive, the positive rate reached to 80.8%; the expression of NF-kappaB in 17 cases was positive, the positive rate reached to 65.4%. Compared with the control group, the difference was statistically significant (p < 0.01). In the experimental group, the expression level of survivin was positively correlated with the positive rate of NF-kappaB. It is concluded that survivin and NF-kappaB widely expressed in lymphoma cells and they play an important role in enhancing proliferation and inhibiting apoptosis of tumor cells.

Evaluation of organ distribution of microcystins in the freshwater phytoplanktivorous fish Hypophthalmichthys molitrix / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

To evaluate the public health risk of exposure to microcystins in fish food in China, the distribution pattern of microcystin-LR and microcystin-RR in various organs (liver, intestine, kidney, muscle and lipid) of the dominant freshwater phytoplanktivorous fish Hypophthalmichthys molitrix in Hangzhou, China's Tiesha River was investigated with the method of HPLC-ESI-MS analysis. The distribution of microcystins was different in the fish organs and the major total microcystins (microcystin-LR and microcystin-RR) were present in the intestines (6.49 micro g/g fresh weight), followed by the livers (4.52 micro g/g fresh weight) and the muscles (2.86 micro g/g fresh weight). Microcystins were detected in kidneys (1.35 micro g/g fresh weight), but not detected in lipid. The results suggested that the mean daily intake from fish was 0.03 micro g/kg body weight which was very close to the recommended WHO tolerable daily intake (TDI) level of 0.04 micro g/kg body weight per day, and local people were warned they may have health risk if they consumed fish from the river.

A case-control family study of gastric cancer in Henan province / 中南大学学报(医学版)

OBJECTIVE@#To explore the risk factors of gastric cancer in the rural area of Henan province.@*METHODS@#Three hundred and twenty-five families with gastric cancer and 325 control families (1010 persons in each group) were selected among the rural residents in 4 counties of Henan province. Totally 2020 people were surveyed and assessed using population-based case-control family study.@*RESULTS@#Gastric cancer was related to stomach upset, irregular dietary, hobby for salty taste, residual food, and history of mental stimulus.@*CONCLUSION@#Stomach upset, irregular dietary, hobby for salty taste, residual food, and history of mental stimulus are the risk factors of gastric cancer.

Iodine excess induces TRAIL expression of thyrocytes in rats / 中华内分泌代谢杂志

Experimental autoimmune thyroiditis (EAT) animal model was established in female SD rats fed with high iodine diet.The concentrations of FT_3 and FT_4 were increasing in order of normal control group, iodine excess control group,EAT control group and EAT iodine excess group (Pl＜0.05 or P＜0.01).Semi- quantitative RT-PCR and Western-blotting results showed that the expression of TNF-related apoptosis-inducing ligand (TRAIL) existed in thyrocytes of each group,while the expression was increasing in order of normal control group,iodine excess control group,EAT control group and EAT iodine excess group (P＜0.01).The results suggested that high iodine diet might induce thyrocytes' apoptosis by increasing the expression of TRAIL and hence influencing functional and pathologic changes of thyroid grand.