Line scanning quantitative analysis method on silicate with small laser beam ( < 15 μm) was developed using laser ablation sector field inductively coupled plasma mass spectrometry (LA-SF-ICP-MS). Differences on signal intensity and elemental fractionation induced by different laser sampling patterns were compared. While spot ablation with small laser beam, the elemental signal intensity decreased with time significantly, and the elemental fractionation was obvious. In contrast, the elemental signal intensity by line scanning was higher and more stable and line scanning was free of elemental fractionation. Therefore, identical ablation pattern and condition should be used for the standard and the unknown sample in LA-ICP-MS quantitative analysis. A single pulse experiment was carried out to investigate the washout time when coupled to two-volume ablation cell. The result indicated that the elemental intensity decayed to the background value needed 2-3 s. The optimal parameters on SF-ICP-MS were set to reduce the effect of signal overlapping. Homogeneous sample KL2-G and titanite grains with composition zoning were analyzed by this method. Accurate element contents and element ratios indicated that fast washout time and optimal instrument parameters made it feasible to perform line scanning quantitative analysis accurately. Comparing to traditional microanalysis, line scanning quantitative analysis could reduce the laser beam size (<15 μm) and improve the spatial resolution efficiently. The potential of the technique to unveil compositional complexities in greater detail would help to improve our understanding of geochemical processes in mineral scale.

OBJECTIVETo investigated the effect of Escherichia coli (Ec) LPS on alkaline phosphatase (ALP) activity and expression of dentin sialophosphoprotein (DSPP) and osteocalcin (OCN) genes in vitro differentiation human dental pulp cell.

METHODSOdontoblast-like cells were cultured, cells exposed to Ec LPS for 12 h, total RNA was isolated and DSPP, OCN transcripts were examined by real-time RT-PCR. ALP kit were used to assessed the changes of ALP activity.

RESULTSReal-time RT-PCR analysis indicated that Ec LPS induced about a 3.6-fold decrease for DSPP gene and a 1.6-fold decrease for OCN gene in odontoblast-like cells as compared with controls. At the same time, cells treated with LPS could depress ALP activity from (1156.10 +/- 100.60) pmol x h(-1) x ng(-1) down to (884.80 +/- 26.72) pmol x h(-1) x ng(-1).

CONCLUSIONSThese results indicate that exposure of odontoblast-like cells to LPS can alter cells function by downregulating cell markers of odontoblastic activity.

Alkaline Phosphatase ; metabolism ; Cell Differentiation ; drug effects ; Cells, Cultured ; Dental Pulp ; cytology ; Escherichia coli ; Humans ; Lipopolysaccharides ; pharmacology ; Minerals ; metabolism ; Odontoblasts ; drug effects ; Osteocalcin ; metabolism

A prokaryotic expression plasmid containing VIP (vasoactive intestinal peptide) and sTNFRII(soluble tumor necrosis factor receptor II ) genes was constructed. The sTNFRII was cloned by PCR by using special primers which contained VIP gene ORF and a linker in its forward primer. The amplified fragment was inserted into the expression vector pET32a between BamHI and Hind III restriction sites. Transformed E.coli DH5 by pET32a-VIP- sTNFRIIexpressed the fusion protein. After being identified, the protein was purified by ion exchange chromatography and by hydrophobic interaction chromatography. The reconstructed protein showed high bio-activity and could be applied for further use.

OBJECTIVETo isolate Nanobacteria from dental pulp stone and perform culturing and the identification of Nanobacteria.

METHODSFreshly collected 27 dental pulp stones were divided into nine samples. Each sample contained three dental pulp stones. All samples were used for the isolation and culture of Nanobacteria. The shape and the growth characteristics of the cultured bacteria were observed. Nanobacteria were identified by von Kossa staining, immunohistochemical staining and indirect immunofluorescence staining, double staining including Hoechst staining and von Kossa staining.

RESULTSThe characteristics growth and morphology of the bacteria detected in seven samples were similar to Nanobacteria. von Kossa staining, immunohistochemical staining, indirect immunofluorescent staining were positive for Nanobacteria. In double staining method, Hoechst staining of the samples was negative for Nanobacteria, but von Kossa staining was positive. Hoechst staining of the dental pulp cells was positive. No Nanobacteria was found in the other two samples.

CONCLUSIONSThe bacteria isolated from dental pulp stone in this study was similar to Nanobacteria in terms of growth rate, morphology and staining properties. These unusual properties of the bacteria may play an important role in the formation of pulp stone.

Bacteria ; isolation & purification ; Dental Pulp Calcification ; microbiology ; Humans ; Immunohistochemistry ; In Vitro Techniques

OBJECTIVETo investigate the current supply and use of personal protective equipment (PPE) among rural-to-urban migrant workers in small and medium enterprises (SMEs) in Zhongshan and Shenzhen, China and the influential factors for the use of PPE, and to provide a basis for better occupational health services and ensuring the health of migrant workers.

METHODSMulti-stage sampling was used to select 856 migrant workers from 27 SMEs in Zhongshan and Shenzhen, and face-to-face questionnaire survey was conducted in these subjects. Statistical analysis was performed by one-way analysis of variance, chi-square test, and logistic regression.

RESULTSOf all migrant workers, 38.67%were supplied with free PPE by the factory, and this rate varied across industries (furniture industry: 45.81%; electronic industry: 31.46%) and SMEs (medium enterprises: 42.13%; small enterprises: 39.20%; micro enterprises: 22.16%); 22.43% insisted on the use of PPE. The logistic regression analysis showed that factors associated with the use of PPE included sex, age, awareness of occupational health knowledge, and the size of enterprise.

CONCLUSIONThe rates of supply and use of PPE among migrant workers are low. The larger the enterprise, the better the supply of PPE. Male gender, being elder, and high occupational health knowledge score were favorable factors for the use of PPE, while small enterprise size was the unfavorable factor for the use of PPE.

Adult ; China ; Female ; Humans ; Male ; Occupational Health Services ; statistics & numerical data ; Protective Devices ; statistics & numerical data ; Rural Population ; statistics & numerical data ; Transients and Migrants ; statistics & numerical data

No abstract available.
Humans ; Interferon-gamma* ; Pityriasis Rosea*

OBJECTIVETo study changes in the levels of systematic and airway local oxidative stress in patients in different stages of chronic obstructive pulmonary diseases (COPD), and explore the association between oxidative stress and glucocorticoid receptor (GR) level in the peripheral blood leukocytes.

METHODSThe levels of malonaldehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) in induced sputum and plasma, as well as GR levels in peripheral blood leukocytes and plasma levels of cortisol and adrenocorticotrophic hormone (ACTH), were examined in 33 patients with acute exacerbations of COPD (AECOPD, group A), 27 with stable COPD (group B), and 28 healthy volunteers (including 15 smokers as group C, and 15 nonsmokers as group D).

RESULTSMDA level in induced sputum and plasma decreased, whereas the levels of GSH, SOD and GSH-PX increased significantly in the order of groups A, B, C, and D (P<0.05). The activity of SOD in induced sputum and plasma were significantly lower in group C than in group D. No significant difference was noted in the other oxidative stress indices between groups C and D (P>0.05). The plasma levels of cortisol and ACTH showed no significant difference between the 4 groups, while the GR level in peripheral blood leukocytes increased significantly in the order of groups A, B, C and D (1565-/+719, 2069-/+488, 2739-/+926, and 4793 -/+1415 U, respectively, P<0.05). After controlling for the factor of smoking status, the plasma and sputum SOD activity were both positively correlated to GR, with the partial correlation coefficient of 0.512 and 0.564, respectively (P<0.001).

CONCLUSIONPatients in different stages of COPD, especially those with AECOPD, may sustain systematic and local oxidation and anti-oxidation imbalance. Decreased SOD activity may contribute to GR level decrement in peripheral blood leukocytes in these patients.

Aged ; Female ; Glutathione Peroxidase ; metabolism ; Humans ; Leukocytes ; metabolism ; Male ; Middle Aged ; Oxidative Stress ; Pulmonary Disease, Chronic Obstructive ; metabolism ; Receptors, Glucocorticoid ; metabolism ; Superoxide Dismutase ; metabolism

OBJECTIVETo explore potential epigenetic biomarkers for toxic effects, tumor-related chemical prevention and biological monitor by a genome-wide screening for differential DNA methylation during human cell malignant transformation in vitro.

METHODSThe two in vitro cell transformation models included B(a)P-induced human bronchial epithelial cell introduced by H-Ras (HBER) cell transformation and simian vacuolating virus 40 small T antigen induced (SV40 ST-induced) HBER cell transformation. Methylated genes were collected by methylated DNA immunoprecipitation and whole genome amplification (MeDIP-WGA) at three time points during cell transformation which represented different transformation stage. Then, CpG island microarray was used to screen differentially methylated genes. The mRNA levels of hypermethylated genes were also observed by RT-PCR.

RESULTSThe CpG island microarray showed that the number of hypermethylated genes in HBER, HBERNT, HBERT cells were 733, 661 and 738 respectively.83 genes were hypermethylated in pre-transformed cell and transformed cell. Moreover, 25 of 83 genes were also hypermethylated in SV40 ST-transformed cell (HBERST). We further confirmed that the mRNA expression of six of these 25 genes, namely family with sequence similarity 178, member A (FAM178A), retinoic acid receptor responder (tazarotene induced) (RARRES1), ubiquitin specific peptidase 28 (USP28), Scm-like with four mbt domains 2 (SFMBT2), family with sequence similarity 59, member A (FAM59A) and nuclear receptor subfamily 4, group A, member 3 (NR4A3) were suppressed during B(a)P-induced transformation.

CONCLUSIONThe abnormal hypermethylation of specific genes was a common event in the two kinds of human cell transformation models, which shed light on the study for chemical exposure monitor and tumor-related epigenetic biomarkers.

Biomarkers ; analysis ; Carcinogens, Environmental ; analysis ; Cell Line ; Cell Transformation, Neoplastic ; genetics ; CpG Islands ; DNA Methylation ; Epigenesis, Genetic ; Gene Expression Profiling ; Genome ; Humans

OBJECTIVETo investigate whether ω-6 polyunsaturated fatty acid promotes colon carcinogenesis through downregulation of P53-dependent growth inhibition.

METHODSColon carcinogenesis was induced by injection of azoxymethane (AOM) intraperitoneally. Experimental animals were randomly divided into four groups, receiving regular diet and intraperitoneal injection of normal saline(control group), high ω-6 polyunsaturated fatty acid diet with intraperitoneal injection of normal saline(Corn oil group), regular diet with intraperitoneal injection of AOM(AOM group), or high ω-6 polyunsaturated fatty acid diet with intraperitoneal injection of AOM (Corn oil+AOM group). Aberrant crypt focis (ACFs) were observed after methylene blue staining and enumerated. Colonic mucosa PCNA and P53 expressions were assessed by RT-PCR and Western blotting, and location of P53 in the colon crypt focis was determined by immunohistochemical staining.

RESULTSAmounts of ACFs was 1.2±0.3 in the control group, 1.3±0.4 in the Corn oil group, 41.0±4.8 in the AOM group, and 73.3±9.9 in the Corn oil+AOM group, the differences were statistically significant(P<0.05). The expression of P53 in normal crypt focis was higher than that in ACFs. High ω-6 polyunsaturated fatty acid dietary significantly promoted AOM-induced colon PCNA expression, and enhanced AOM-mediated P53 inhibition in colon mucosa.

CONCLUSIONHigh ω-6 polyunsaturated fatty acid diet can enhance AOM-induced inhibition of P53 in colon mucosa, resulting in overexpression of PCNA, formation of ACF, and carcinogenesis in the colon.

Animals ; Colon ; drug effects ; metabolism ; Fatty Acids, Unsaturated ; adverse effects ; Intestinal Mucosa ; drug effects ; metabolism ; Male ; Proliferating Cell Nuclear Antigen ; metabolism ; Rats ; Rats, Sprague-Dawley ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVETo evaluate the diagnosis and surgical treatment of obstructive azoospermia.

METHODSWe analyzed the clinical data of 56 cases of obstructive azoospermia, 43 of them with ejaculatory duct obstruction (EDO), and the other 13 suspected of epididymal obstruction. The diagnostic methods included semen analyses, measurement of fructose and neutral alpha-glucosidase in the seminal plasma, transrectal ultrasonography (TRUS), and vasography when necessary. The 43 patients with EDO were treated by transurethral resection of the ejaculatory duct (TURED), and 11 of the 13 cases of suspected epididymal obstruction were confirmed by scrotal exploration and underwent either bilateral or unilateral vasoepididymostomy. The patients were followed up for 3 -51 months for postoperative semen quality and impregnation.

RESULTSOf the 43 azoospermia patients with EDO treated by TURED, 36 (83.7%) showed improved semen parameters and 11 (25.6%) achieved pregnancies. Among the 11 cases of azoospermia with confirmed epididymal obstruction treated by vasoepididymostomy, 6 (54.5%) had sperm in the semen assay and 3 (27.3%) achieved pregnancies.

CONCLUSIONSemen analyses, measurement of fructose and neutral alpha-glucosidase in the seminal plasma, TRUS and vasography are important diagnostic methods for obstructive azoospermia. TURED is effective for azoospermia with EDO, while vasoepididymostomy is preferable for the treatment of azoospermia with epididymal obstruction.

Adult ; Azoospermia ; etiology ; surgery ; Epididymis ; pathology ; surgery ; Humans ; Male ; Radiography ; Rectum ; diagnostic imaging ; Treatment Outcome ; Ultrasonography ; Vas Deferens ; diagnostic imaging ; surgery