OBJECTIVETo seek effective drugs for anti-hepatitis C virus by screening 20 Chinese herbs often used for clearing heat and dissipating toxin with nude mice model of hepatitis C viral (HCV) infection.

METHODSAfter the model mice had been treated with selected drug for 3 months, transmission electron microscope was used to observe whether the HCV-like particles in human fetal hepatocytes (HFH) transplanted into mice spleen still existed, and quantitative RT-PRC technique was used to detect the serum content of HCV-RNA before and after treatment.

RESULTS(1)HCV-like particles existed in all the model mice after treatment. (2) Serum content of HCV-RNA decreased after treated with Radix Gentianae, Radix Scutellariae, Radix Sophorae tonkinensis, Fructus Gardeniae and Fructus Sophorae flavoscentis, but unchanged after treatment with other drugs.

CONCLUSIONAll the 20 herbs screened has not effect in directly eradicating HCV, but Radix Gentianae, Radix Scutellariae, Radix Sophorae tonkinensis, Fructus Gardeniae and Fructus Sophorae flavoscentis could significantly inhibit the replication of HCV-RNA.

Animals ; Antiviral Agents ; pharmacology ; Drug Evaluation, Preclinical ; Drugs, Chinese Herbal ; pharmacology ; Female ; Gentiana ; chemistry ; Hepacivirus ; drug effects ; Hepatitis C ; virology ; Male ; Mice ; Mice, Nude ; Phytotherapy ; Scutellaria baicalensis ; chemistry ; Sophora ; chemistry ; Virus Replication ; drug effects

The high-copy-number plasmid pcDNA3.1+ is unstable within S almonella typhimurium. A novel plasmid pmcDNA3.1+ was constructed by removin g the promoter sequence of ampicillin resistance gene (bla gene) in plasmid pcDNA3.1+. In contrast to pcDNA3.1+, pmcDNA3.1+ was stable within Salmonel la typhimurium SL7207 in LB medium with or without ampicillin. Further experi ments showed the ?-lactamase activity of Salmonella typhimurium SL7207(pmc DNA3.1+) was apparently lowered than that of Salmonella typhimurium SL7207( pcDNA3.1+) and the high ampicillin concentration was maintained longer in LB me dium culturing Salmonella typhimurium SL7207(pmcDNA3.1+). When mice were a dministered with Salmonella typhimurium SL7207(pmcDNA3.1+) intraperitoneall y, more than 95% of Salmonella cells separated from the spleen still harbore d the plasmid pmcDNA3.1+ 7 days later; but 99% of Salmonella cells lost the plasmid pcDNA3.1+ at day 3 in mice innoculated with Salmonella typhimurium SL7207(pcDNA3.1+). By lowering the expression of bla gene, the rapid deco mposition of ampicillin in LB medium was avoided and the metabolic pressure was relieved for the host cells. This method offers a solution for the problem of t he instability of high-copy-number plasmid within Salmonella typhimurium.

A laccase gene (lacD) from the basidiomycete Trametes sp. 420 was heterologously expressed in Pichia pastoris in two ways, resulting in two recombinant enzymes of rLacDx with native N-terminus and rLacDe with eight additional amino acid residues at N-terminus. The yields of rLacDx and rLacDe in shaken-flask cultures after an 18-day growth were 1.21 x 10(5) u/L and 7.38 x 10(4) u/L, respectively, as determined with 2,2'-azinobis(3-ethylbenzothia-zoline- 6-sulfonic acid) (ABTS) as substrate. The yield of rLacDx was further increased to 2.39 x 10(5) u/L under high-density fermentation while the production process was decreased to 7.5 days. In addition, rLacDx and rLacDe exhibited similar enzymatic characters in oxidizing substrate guaiacol, and were stable at 50 degrees C and at a pH range from 3 to 10. However, the specific activity of rLacDx (1761 u/mg) for ABTS was higher than that of rLacDe (1122 u/mg), and the apparent Km value of rLacDx (427 microM) was less than that of rLacDe (604 microM).
Cloning, Molecular ; Fermentation ; Isoenzymes ; biosynthesis ; genetics ; Laccase ; biosynthesis ; genetics ; Pichia ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; Trametes ; enzymology ; genetics

OBJECTIVETo evaluate accuracy of Propex, Raypex 5, Root ZX electronic apex locator in positions of the perforation with different irrigations in the root canal.

METHODSPerforation lengths were measured with Propex, Raypex 5, Root ZX electronic apex locators in 19 extracted human teeth embedded in model after simulate perforation preparation by ultrasonic ET40 and compared with the actual canal length measurements taken before embedding the teeth in model. Measurements were taken with the different canal contents. RESULTS; Propex, Raypex 5, and Root ZX could locate the positions of the perforation with different irrigations in the root canal. The differences between actual root canal perforation length and measured root canal perforation length of same electronic apex locators in different irrigations were no statistically significant (P > 0.05). Meanwhile, the differences between actual root canal perforation length and measured root canal perforation length of three kinds of electronic apex locators in same irrigations were not statistically significant (P > 0.05).

CONCLUSIONPropex, Raypex 5, and Root ZX electronic apex locators can detect perforation accurately.

Dental Pulp Cavity ; Humans ; In Vitro Techniques ; Molar ; Odontometry ; Root Canal Therapy ; Tooth Apex ; Tooth Root

OBJECTIVETo study the significance of c-myc, p53 and p16 protein expression in fibrous dysplasia, to detect the GNAS1 gene mutation in fibrous dysplasia, and to explore the property of fibrous dysplasia.

METHODSThe expression of c-myc, p53 and p16 protein was evaluated by immunohistochemistry SP method in 35 cases of fibrous dysplasia including 1 FD with malignancy, 1 Mazabraud syndrome and 20 control cases (10 cases of bony callus, 10 cases of osteosarcoma). Genomic DNA extraction, PCR amplification and gene sequencing were used to detect GNAS1 gene mutation in 35 cases of fibrous dysplasia.

RESULTSC-myc protein immunoreactivity was detected in 91 percentage of FD (P = 0.001). Compared with the negative control group, the difference was significant. P16 positive was detected in 34 FD cases (P = 0.001). The difference was significant as compared with the positive control group. Positive p53 protein expression was detected in the only 1 case of fibrous dysplasia with malignant transformation. PCR amplification was successful in 12 of 35 FD cases. Two of the 12 FD cases were detected to have GNAS1 gene mutation, in which 1 case was FD of Mazabraud syndrome, 1 case was a monostotic lesion.

CONCLUSIONSC-myc could be another protooncogene in addition to c-fos in the fibrous dysplasia disease. P53 protein overexpression could be useful in the diagnosis of FD malignancy and in the prediction of the prognosis of FD. The abnormal expression of the gene p16 might play an important role in the formation of FD. The GNAS1 mutation exist in FD. All of the results indicate that FD could be a neoplasia disease, caused by multiple factors leading to a dysfunction of bone development.

Adolescent ; Adult ; Child ; Chromogranins ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Female ; Fibrous Dysplasia of Bone ; genetics ; metabolism ; pathology ; GTP-Binding Protein alpha Subunits, Gs ; genetics ; Humans ; Male ; Middle Aged ; Mutation ; Osteosarcoma ; genetics ; metabolism ; pathology ; Proto-Oncogene Proteins c-myc ; metabolism ; Tumor Suppressor Protein p53 ; metabolism ; Young Adult

OBJECTIVEThe purpose of this article is to examine the effect of curcumin on the proliferation and metastasis of human tongue squamous cell carcinoma and analyze its mechanism.

METHODSSCC-4 were treated with curcumin of 0, 5, 10, 20, 30, 60, 100 micromol x L(-1) in 24 h. MTT assay, Matrigel invasion assay, flow cytometry and fluorescence microscopy were used to examine the effect of curcumin on the growth and metastasis of SCC-4. cDNA microarray and RT-PCR were employed to analyze the expression of genes treated by curcumin.

RESULTSThe results showed that curcumin could concentration-dependently inhibit SCC-4 cell proliferation at the concentration range from 20 to 100 micromol x L(-1). Furthermore, Matrigel invasion assay indicated that curcumin can reduce SCC-4 cell invasion under the dosage of 20, 30, 60 micromol x L(-1). Flow cytometry also showed that curcumin can influence the distribution of cell cycle of SCC-4 cell with the dosage of 20, 30, 60 micromol x L(-1). And the dosage of 30 micromol x L(-1) curcumin could lead to the recruitment of alpha-tubulin. cDNA microarray showed that 87 genes were activated and 198 genes were inhibited with the effect of curcumin. These results were validated by the real time quantitative RT-PCR.

CONCLUSIONAccording to the results, it suggests that curcumin has the potential as the leading compound for anti-cancer proliferation and invasion in oral cancer treatment, and cdc27, EGFR substrate 15, PPAR-alpha and H2A histone may play an important role among this multiple anticancer-targeting ability.

Cell Line, Tumor ; Cell Proliferation ; Curcumin ; Humans ; Mouth Neoplasms

BACKGROUNDAzithromycin can reduce neutrophil accumulation in neutrophilic pulmonary diseases. However, the precise mechanism behind this action remains unknown. Our experiment assessed whether azithromycin inhibits neutrophil accumulation in the airways by affecting interleukin-17 (IL-17) downstream signals.

METHODSMice were pretreated with azithromycin before murine IL-17A (mIL-17) stimulation. After the mIL-17 stimulation, the levels of six neutrophil-mobilizing cytokines were determined by enzyme-linked immunosorbent assay (ELISA) tests in bronchoalveolar lavage (BAL) fluid; IL-6, CXC chemokine ligand-1 (CXCL-1), CXCL-5, macrophage inflammatory protein-2 (MIP-2), granulocyte colony-stimulating factor (G-CSF), and granulocyte macrophage colony-stimulating factor (GM-CSF). The number of neutrophils in BAL fluid were evaluated by cytospin preparations.

RESULTS(1) Azithromycin pretreatment significantly inhibited both the release of three neutrophil-mobilizing cytokines (MIP-2, CXCL-5 and GM-CSF) and the accumulation of neutrophils in airways caused by mIL-17 stimulation. (2) The levels of three neutrophil-mobilizing cytokines (IL-6, MIP-2 and GM-CSF) were positively correlated with the numbers of neutrophil in BAL fluid.

CONCLUSIONSAzithromycin can inhibit neutrophil accumulation in the airways by affecting IL-17 downstream signals. This finding suggests that macrolide antibiotic application might be useful in prevention of neutrophilic pulmonary diseases characterized by high levels of IL-17.

Animals ; Azithromycin ; pharmacology ; Bronchoalveolar Lavage Fluid ; chemistry ; Chemokine CXCL2 ; metabolism ; Chemokines, CXC ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Granulocyte Colony-Stimulating Factor ; metabolism ; Granulocyte-Macrophage Colony-Stimulating Factor ; metabolism ; Interleukin-17 ; pharmacology ; Interleukin-6 ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Neutrophils ; drug effects ; metabolism

OBJECTIVETo investigate the transcription level and protein expression of HIF-1alpha and VEGF in SW480 cell line and colorectal adenocarcinoma, and to determine whether HIF-1alpha plays a role in angiogenesis through its regulation of VEGF.

METHODSHIF-1alpha mRNA expression was analyzed by in situ hybridization. HIF-1alpha and VEGF protein expressions were determined by immunochemical streptavidin/peroxidase (SP) in SW480 cells and colorectal carcinoma tissue samples and Western blot, using proteins extracted from SW480 cells. Tumor tissue microvessel density (MVD) was determined by CD34 immunostaining of colorectal carcinomas.

RESULTSThe levels of HIF-1alpha mRNA changed significantly in response to different oxygen concentrations and an addition of genistein in SW480 cells. Immunocytochemistry revealed that the levels of HIF-1alpha, VEGF protein expression in SW480 cells were significantly higher under hypoxia than those in nomoxia (P < 0.01, P < 0.05 respectively). However, addition of genistein, an inhibitor of HIF-1alpha, suppressed such responses to hypoxia. Western blot analysis showed that SW480 cells exposed to hypoxia expressed a high level of HIF-1alpha protein, compared to a weak expression in nomoxia. The addition of genistein in hypoxia suppressed the over-expression of HIF-1alpha. The positive rates of HIF-1alpha mRNA by in situ hybridization in colorectal adenomas and adenocarcinomas were 38.9% (7/18) and 67.7% (42/62), respectively. The percentage of HIF-1alpha mRNA positive cells varied significantly from colorectal adenomas to adenocarcinomas at different Duke stages (P < 0.05), and HIF-1alpha mRNA was higher in adenocarcinomas than in adenomas (P < 0.01). The positive rates of HIF-1alpha and VEGF protein expression in adenocarcinomas were 43.5% (27/62) and 37.1% (23/62), respectively. The expression of VEGF elevated as the Duke tumor staging increased. The conformation rate of HIF-1alpha and VEGF was 74.2% (46/62). MVD was significantly higher in HIF-1alpha and/or VEGF positive tumors than those without (P < 0.01 and P < 0.05 respectively). Among the four groups, i.e. HIF-1alpha+/VEGF+, HIF-1alpha+/VEGF-, HIF-1alpha+/VEGF- and HIF-1alpha-/VEGF-, the difference of MVD was highly significant (P < 0.01). HIF-1alpha expression was correlated significantly with VEGF expression and microvessel density.

CONCLUSIONSThese findings suggest hypoxia induces the expression of HIF-1alpha and VEGF in colorectal adenocarcinoma. HIF-1alpha may play an important role in angiogenesis and tumor progression by regulating the expression of VEGF in human colorectal carcinoma.

Adenocarcinoma ; blood supply ; metabolism ; pathology ; Colorectal Neoplasms ; blood supply ; metabolism ; pathology ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; Microcirculation ; pathology ; Neovascularization, Pathologic ; etiology ; RNA, Messenger ; biosynthesis ; genetics ; Transcription Factors ; biosynthesis ; genetics ; Tumor Cells, Cultured ; Vascular Endothelial Growth Factor A ; biosynthesis ; genetics

For determination the ionic mechanisms of the hypoxic acclimatization at the level of channels, male Spradue-Dawley rats were divided into two groups: control normoxic group and chronic intermittent hypoxic group [O2 concentration: (10 +/-0.5)%, hypoxia 8 h a day]. Using whole cell patch-clamp technique, voltage-gated potassium channel currents (IK(V)) were recorded in freshly isolated pulmonary arterial smooth muscle cells (PASMCs) of rat with acute isolated method. The effect of acute hypoxia on IK(V) of PASMCs from chronic intermittent hypoxia group was investigated to offer some basic data for clarifying the ionic mechanisms of the hypoxic acclimatization. The results showed: (1) In control normoxic group, after acute hypoxia free-Ca(2+) solution, the resting membrane potential (Em) of PASMCs was depolarized significantly from -47.2+/-2.6 mV to -26.7+/-1.2 mV, and the IK(V) of PASMCs was decreased significantly from 153.4+/-9.5 pA/pF to 70.1+/-0.6 pA/pF, the peak current percent inhibition was up to (57.6+/-3.3)% at +60 mV, and current-voltage relationship curve shifted to the right. (2) In chronic intermittent hypoxic group, the IK(V) of PASMCs was decreased significantly by exposure to intermittent hypoxia in a time-dependent manner, appeared to start on day 10 and continued to day 30 (the longest time tested) of hypoxia, and current-voltage relationship curve shifted to the right in a time-dependent manner. (3) Compared with the control normoxic group, the percent IK(V) inhibition by acute hypoxia was significantly attenuated in the chronic intermittent hypoxia group and this inhibition effect declined with time exposure to hypoxia. The results suggest that K(V) inhibition was significantly attenuated by chronic intermittent hypoxia, and this effect may be a critical mechanism of the body hypoxic acclimatization.
Animals ; Cell Separation ; Hypoxia ; complications ; physiopathology ; Male ; Muscle, Smooth, Vascular ; cytology ; metabolism ; physiology ; Potassium Channels, Voltage-Gated ; antagonists & inhibitors ; Pulmonary Artery ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley

BACKGROUND AND OBJECTIVESince the proposal of the tumor stem cell hypothesis, considerable interest has been devoted to the isolation and purification of tumor stem cells. Tumor stem cell enrichment from primary tumor derived cell spheres has been demonstrated in specific, serum-free media. This goal of this study is to establish a method of cultivating floating tumor spheres from neuroblastoma cells and to confirm that neuroblastoma spheres are rich in tumor stem cells.

METHODSBone marrow aspirates were obtained from pediatric patients diagnosed with stage IV neuroblastoma. Primary tumor cells were isolated and cultivated in serum-free, stem cell-selective medium. Single sphere-forming cells were cultivated under serum-free conditions; their cloning efficiency and monoclonal tumor sphere formation rates were calculated. The expression of stem cell marker genes Oct-4 and Bmi-1 was detected by RT-PCR in sphere-forming cells and parental neurolastoma cells. Sphere-forming cells were injected into the armpit of nude mice with subsequent assessment for tumor growth. Sphere-forming cells were cultivated in differentiation medium containing 5 μmol/L 13-cis retinoic acid; changes in cell morphology were observed.

RESULTSNeuroblastoma cells formed non-adherent neurospheres under serum-free, stem cell-selective conditions after a period of 4 to 6 days. A single cell dissociated from a neurosphere could reform a monoclonal sphere; cloning efficiency and monoclonal sphere formation rates were 55.3% and 26.3%, respectively. RT-PCR results revealed heightened tumor sphere expression of Oct-4 and Bmi-1 as compared with parental tumor cells. Fourteen days after injection of 10(4) sphere-forming cells into nude mice, a neuroblastoma xenograft formed. Treatment of sphere-forming cells with 13-cis retinoic acid induced a gradual differentiation to neuronal cell morphology.

CONCLUSIONSNeuroblastoma derived tumor spheres enrich tumor stem cells and the cultivation of primary neuroblastoma cells in serum-free, stem cell-selective medium is an effective method to dissociate and purify tumor stem cells in vitro.

Animals ; Cell Culture Techniques ; methods ; Cell Differentiation ; drug effects ; Child ; Culture Media, Serum-Free ; Humans ; Isotretinoin ; pharmacology ; Mice ; Mice, Nude ; Neoplasm Transplantation ; Neoplastic Stem Cells ; metabolism ; pathology ; Neuroblastoma ; metabolism ; pathology ; Nuclear Proteins ; metabolism ; Octamer Transcription Factor-3 ; metabolism ; Polycomb Repressive Complex 1 ; Proto-Oncogene Proteins ; metabolism ; Repressor Proteins ; metabolism ; Spheroids, Cellular ; pathology ; Xenograft Model Antitumor Assays