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 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 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 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 evaluate the diagnostic value of multi-slice spiral CT (MSCT) three dimensional (3D) reconstruction for maxillofacial diseases.

METHODSSixty patients with maxillofacial diseases underwent the scanning of MSCT with 3D reconstruction. Among them, 34 patients with maxillofacial fracture, 10 patients with maxillofacial tumors and tumor-like diseases, and 16 patients with congenital deformities. The MSCT scanned with slice thickness of 2 mm. The methods of 3D reconstruction included multi-planar reconstruction (MPR), shaded surface display (SSD), and volume rendering (VR). The results were compared with what was observed during operations.

RESULTSTotally 36 cases of maxillofacial fracture were shown by 2D or 3D imaging and were validated by the observations during operation. The MSCT with 3D reconstruction imaging was significantly superior to 2D axial imaging in maxillofacial fracture. Three dimensional imaging could clearly show the spacial anatomy of facial, fragment displacement, and tracing fracture lines. However, 2D imaging had better effectiveness than 3D imaging in observing deep structure and fine fracture. In maxillofacial tumors and tumor-like diseases, 3D imaging was significantly superior to 2D axial imaging in showing the tumor shape and spacial relationships between tumors and surrounding structures. Two dimensional imaging and MPR imaging were excellent to reveal internal structure and pathological changes of tumors. 2D imaging and MPR imaging also achieved better results in showing tumors extended to soft tissues. In maxillofacial congenital deformities, 3D imaging were superior than 2D imaging.

CONCLUSION3D imaging has an important value in the diagnosis and clinical assessment of maxillofacial fracture, tumor-like diseases, and congenital deformities.

Adolescent ; Adult ; Child ; Female ; Humans ; Imaging, Three-Dimensional ; methods ; Male ; Mandibulofacial Dysostosis ; diagnostic imaging ; Maxillofacial Abnormalities ; diagnostic imaging ; Maxillofacial Injuries ; diagnostic imaging ; Sensitivity and Specificity ; Tomography, Spiral Computed ; methods

OBJECTIVETo investigate the effects of intrathecal ouabain and tizanidine injection for treatment of neuropathic pain in rats.

METHODSMale SD rats weighing 250-300 g were randomly divided into 5 groups (n = 6), namely the control group, ouabain group, tizanidine group, combined ouabain and tizanidine injection group, and the antagonist group. Intrathecal catheter was implanted 7 days before spinal nerve ligation to establish the neuropathic pain model. Mechanical withdrawal threshold (MWT) before and after intrathecal administration of the agents was recorded in the rats. Isobolographic analysis was performed to evaluate the interactions between the agents.

RESULTSIntrathecal injection of ouabain (0.25-5 microg) or tizanidine (0.5-5 microg) alone produced dose-dependent analgesic effect against the neuropathic pain (P < 0.05). Isobolographic analysis revealed a synergistic interaction between ouabain and tizanidine. Intrathecal pretreatment with atropine (5 microg) or yohimbine (20 microg) antagonized the effects of ouabain and tizanidine administered alone or in combination (P < 0.05).

CONCLUSIONIntathecal injection of ouabain or tizanidine produces dose-dependent analgesic effects against neuropathic pain, and their synergistic effect after combined injection probably involves the cholinergic transmission and alpha2 receptor.

Analgesics ; administration & dosage ; Animals ; Clonidine ; administration & dosage ; analogs & derivatives ; Injections, Spinal ; Ouabain ; administration & dosage ; Pain ; drug therapy ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spinal Nerves ; injuries

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

OBJECTIVETo analyze the global gene expression profile of primary cultured nasopharyngeal carcinoma (NPC) cells using cDNA microarray techniques to screen new candidate genes related to the occurrence and progression of NPC.

METHODSA NPC cell line C666 and primary cultured NPC cells from biopsy specimens in 5 cases were analyzed with microarray techniques in comparison with 3 normal nasopharyngeal epithelial (NPE) biopsy specimens. Several differentially expressed genes identified from the microarray results were verified by fluorescence real-time PCR (FQ-PCR) and immunohistochemistry (IHC).

RESULTSPrimary cultured cells of both NPC and NPE were verified by cytokeratin IHC, EBER1 in situ hybridization and EBV-DNA real-time PCR. Compared with NPE cells, a total of 493 genes in at least 4/6 of the samples were identified to be differentially expressed in the primary cultured NPC cells, including 264 up-regulated and 229 down-regulated ones. Several differentially expressed genes according to the microarray results were confirmed by real-time PCR and IHC.

CONCLUSIONcDNA microarray technique provides an effective and accurate means for global gene expression profiling of primary cultured NPC cells to screen the differentially expressed genes, which may serve as an important basis for studying the mechanism, classification and diagnosis of NPC at the molecular level.

Animals ; Cells, Cultured ; Gene Expression Profiling ; Humans ; Immunohistochemistry ; Nasopharyngeal Neoplasms ; genetics ; pathology ; Oligonucleotide Array Sequence Analysis ; Polymerase Chain Reaction ; RNA ; isolation & purification