Trypanosoma is a human parasite severely affecting poor tropical areas.However,current frontline drugs for Trypanosoma treatment have severe side-effects with decreased effectiveness.Based on the fact that aminoacyl-tRNA synthetase is a bonafide drug target for several microorganisms,including bacteria and fungi,it is plausible that it may also be effective target of Trypanosoma.The Trypanosoma brucei leucyl-tRNA synthetase(tbLeuRS)was cloned,expressed and purified to develop an in vitro enzymatic assay system.The assay conditions were further optimized for the effective screening of tbLeuRS inhibitors thus establishing an anti-Trypanosoma drug screening system targeting tbLeuRS.The results indicated that this system can be employed for the effective screening of anti-Trypanosoma drugs with satisfactory specificity.In addition,this system can also be used for compound optimization,as well as IC50 testing.Using this system a series of compounds are identified that are effective Trypanosoma inhibitors without toxicity to human cells.Therefore,targeting tbLeuRS may represent a new venue for the development of anti-Trypanosoma drugs.

Objective To investigate the clinical significance of procalcitonin(PCT) in early diagnosis of neonatal infections.Methods Rapid hemi-quantitative immunoassay was used to measure PCT levels in 196 hospitalized neonates, who were divided into sepsis group,(local-)infection group, virus-infection group and non-infection group.Results If plasma PCT≥0.5 ?g/L was taken as positive,the positive rates in sepsis group,local-infection,virus-infection,non-infection group were 87.87%,41.66 %,12.0%,11.11%,respectively.The positive rate of sepsis group was significantly higher than that of the other 3 groups(all P

Objective: To study common problems in BRAF gene mutation detection, and conditions for repetition testing using thyroid fine needle aspiration specimens. Methods: A total of 8 644 cases of thyroid fine-needle aspiration specimens at China-Japan Friendship Hospital were collected between February, 2012 and July, 2018. BRAF gene mutation was detected by real-time PCR. Repeat testing was performed in 237 cases when the results were inconsistent with clinical or cytological diagnosis or when uncertain results were obtained. Results: The final positive rates of BRAF mutation was 22.0% (1 897/8 625). Nineteen cases were excluded due to inadequate DNA samples. The average Ct value of internal quality control was 16.061, and the average Ct value of the positive samples was 19.147. Among 237 repeat tests, 51.4% (19/37) continued to have poor DNA quality and 48.6% (18/37) had adequate DNA resulting in 1 positive case and 17 negative cases. In 40 repetition of initial negative cases, results were unchanged. In initial positive cases, 40.4% (40/99) with a difference of Ct value (between BRAF gene and internal quality control) between 8 to 12 turned negative after repetition, 69.8% (37/53) of these cases with a difference of more than 12 turned negative after repetition. The sensitivity and specificity of BRAF mutation were 83.97% and 96.94%, respectively. Conclusions Difference between BRAF gene Ct value and internal quality control Ct value is recommended as a reliability index for the test result. Cases with a difference greater than 8 should be subjected to repeat testing.

study common problems in BRAF gene mutation detection, and conditions for repetition testing using thyroid fine needle aspiration specimens. Methods A total of 8 644 cases of thyroid fine?needle aspiration specimens at China?Japan Friendship Hospital were collected between February, 2012 and July, 2018. BRAF gene mutation was detected by real?time PCR. Repeat testing was performed in 237 cases when the results were inconsistent with clinical or cytological diagnosis or when uncertain results were obtained. Results The final positive rates of BRAF mutation was 22.0% (1 897/8 625). Nineteen cases were excluded due to inadequate DNA samples. The average Ct value of internal quality control was 16.061, and the average Ct value of the positive samples was 19.147. Among 237 repeat tests, 51.4% (19/37) continued to have poor DNA quality and 48.6% (18/37) had adequate DNA resulting in 1 positive case and 17 negative cases. In 40 repetition of initial negative cases, results were unchanged. In initial positive cases, 40.4% (40/99) with a difference of Ct value (between BRAF gene and internal quality control) between 8 to 12 turned negative after repetition, 69.8% (37/53) of these cases with a difference of more than 12 turned negative after repetition. The sensitivity and specificity of BRAF mutation were 83.97% and 96.94%, respectively. Conclusions Difference between BRAF gene Ct value and internal quality control Ct value is recommended as a reliability index for the test result. Cases with a difference greater than 8 should be subjected to repeat testing.

OBJECTIVETo investigate the clinical effects and prevent the complications of posterior and anterior decompression and internal fixation in the revision of cervical anterior internal fixation failure.

METHODSFrom 2008 January to 2011 December, 17 patients with cervical anterior internal fixation failure were treated with posterior and anterior decompression and internal fixation. There were 12 males and 5 females, aged from 26 to 68 years old with an average of 44.1 years. The lower screw loosening was found in 6 cases, the upper screw loosening in 5 cases, titanium mesh caving in 3 cases, the upper screw breakage in 2 cases, the lower screw breakage in 1 case. Informations of bone fusion were observed by X-ray, CT, MRI. Clinical effects were evaluated by modified JOA score.

RESULTSAll the revision operations were successfully completed. One case with poor blood coagulation function before operation resulted in postoperative hematoma and occurred neurological symptoms; after hematoma removal and fresh frozen plasma infusion later, neurological symptoms of the patient disappeared. All patients were followed up from 6 to 38 months with an average of (22.4±10.0) months. Postoperative at 2 weeks, 3 months, and final follow-up, JOA score had obviously improved and respectively was 13.1±1.6, 13.4±1.6, 14.2±1.5. All internal fixation locations were good after revision,and obtained bone fusion at 10 months after operation, with an average fusion time of 6 months.

CONCLUSIONThe combined posterior and anterior decompression and internal fixation in the revision of cervical anterior internal fixation failure is safe, can achieve thoroughly decompression, maintain the cervical curvature, reconstruct the three column stability, and it may be used for the patients of cervical anterior fixation failure.

Adult ; Aged ; Cervical Vertebrae ; surgery ; Decompression, Surgical ; methods ; Female ; Fracture Fixation, Internal ; methods ; Humans ; Male ; Middle Aged

OBJECTIVETo investigate the activation pattern of signal transducers and activators of transcription (STAT) induced by vascular endothelial growth factor (VEGF) in CD34+ hematopoietic progenitor cells, and gain an insight into the molecular mechanism and signal transduction pathway of VEGF that has an effect on CD34+ hematopoietic progenitor cells.

METHODSAfter isolated from umbilical cord blood by using a high-gradient magnetically activated cell sorting system (MACS), CD34+ cells were stimulated by VEGF (50 ng/ml) for different time (0, 15, 30, 45, 60, 90 min) to detect the tyrosine phosphorylation and nuclear translocation of STAT-3 and STAT-5 with Western blot and immunocytochemistry methods. The expression of VEGF receptor-2 (VEGFR2) on the membrane of CD34+ progenitor cells was examined by immunocytochemistry. ATWLPPR, an effective peptide screened from phage epitope library by affinity for membrane-expressed VEGFR2 and blocking the binding of VEGF to VEGFR2, was used to determine whether the activation of STAT pathway induced by VEGF was blocked.

RESULTSTyrosine phosphorylation of STAT-3 and STAT-5 was undetectable in unstimulated CD34+ cells, but was evident at 15 min in response to VEGF stimulation. VEGF resulted in a rapid and transient tyrosine phosphorylation of STAT-3 and STAT-5. The maximal tyrosine phosphorylation was catched at 30 and 45 min, respectively (P = 0.0001), and returned to basal levels at 90 min. Immunocytochemistry confirmed that increased phosphorylated STAT-3 was translocated into the nuclei at 30 min (P = 0.0001), and mainly in cytoplasms again at 90 min after stimulation with VEGF. However, compared with unstimulated CD34+ cells, there was only increased phosphorylation of STAT-5 appeared mainly in cytoplasms, but no significant nuclear translocation was found after stimulation with VEGF (P > 0.05). The presence of VEGFR2 was confirmed using anti-VEGFR2 antibody staining by immunocytochemistry, moreover, the phosphorylation of STAT-3 and STAT-5 failed to be activated by the co-culture with ATWLPPR and VEGF, suggesting that activation of the STAT pathway be specifically mediated by VEGFR2 in CD34+ progenitor cells.

CONCLUSIONSSTAT signaling pathway participates in the signal transduction of VEGF via VEGFR2 in CD34+ hemopoietic progenitor cells.

Adult ; Antigens, CD34 ; metabolism ; DNA-Binding Proteins ; Endothelium, Vascular ; drug effects ; metabolism ; Female ; Fetal Blood ; cytology ; Hematopoietic Stem Cells ; metabolism ; physiology ; Humans ; Milk Proteins ; Phosphorylation ; Pregnancy ; Receptors, Vascular Endothelial Growth Factor ; metabolism ; STAT3 Transcription Factor ; STAT5 Transcription Factor ; Signal Transduction ; Trans-Activators ; metabolism ; Transcription, Genetic ; Tyrosine ; metabolism ; Vascular Endothelial Growth Factor A ; pharmacology

OBJECTIVETo investigate the effects of vascular endothelial growth factor (VEGF) on differentiation and function of dendritic cells derived from CD34+ hematopoietic progenitor cells.

METHODSAfter isolation from umbilical cord blood with a high-gradient magnetic cell sorting system (MACS), the CD34+ cells were cultured with a cocktail cytokines for differentiating into dendritic cells (DC). The cells were stimulated by VEGF (25 ng/ml) either at the beginning or at day 9 of culture. Kinetics analysis of cell proliferation was performed during the process of cell culture, and the expression of DC differentiation antigens including CD1alpha, CD83, CD80, CD54 and HLA-DR was examined by flow cytometry. DC function was evaluated by the ability to induce proliferation of allogeneic T cells in mixed lymphocyte reaction (MLR) assay, and the production of IL-12 by ELISA.

RESULTSVEGF added at day 1 of culture induced an increase of total cell numbers by (1.51 +/- 0.23)-folds (P = 0.001). VEGF added at the initial but not the late stage of culture could dramatically down-regulate the expression of CD1a [(33.00 +/- 2.12)% vs (81.20 +/- 6.93)%], CD83 [(42.23 +/- 1.15)% vs (87.98 +/- 7.97)%], CD80 (42.93 +/- 1.32)% vs (94.53 +/- 0.87)%], and HLA-DR [(37.93 +/- 5.30)% vs (74.15 +/- 3.74)%], while obviously up-regulate the expression of CD14. Moreover, the inhibitory effect of VEGF on DC function was confirmed by a reduced ability to induce proliferation of allogeneic T cells and production of IL-12 (P < 0.01).

CONCLUSIONSVEGF could induce the expansion of hematopoietic progenitor cells and inhibit at the early stage their differentiation into mature DC.

Antigens, CD ; analysis ; Antigens, CD1 ; analysis ; Antigens, CD34 ; analysis ; blood ; B7-1 Antigen ; analysis ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Dendritic Cells ; cytology ; immunology ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Fetal Blood ; cytology ; immunology ; Flow Cytometry ; HLA-DR Antigens ; analysis ; Hematopoietic Stem Cells ; cytology ; immunology ; metabolism ; Humans ; Immunoglobulins ; analysis ; Intercellular Adhesion Molecule-1 ; analysis ; Interleukin-12 ; analysis ; Membrane Glycoproteins ; analysis ; Vascular Endothelial Growth Factor A ; pharmacology

OBJECTIVETo investigate the expression of OPCML gene in ovarian epithelial carcinoma and determine the relationship between mRNA expression and methylation of their promoters.

METHODTwenty normal ovarian tissues and 89 ovarian epithelial tumor specimens (72 malignant, 17 benign), as well as 3 ovarian carcinoma cell lines (SKOV-3, CAOV3, and 3AO), were collected for detection of OPCML gene expression by reverse transcription-polymerase chain reaction and for detection of promoter methylation by restriction enzyme cut analysis from 7. 1999 to 7. 2003.

RESULTSAmong ovarian epithelial carcinoma 19.4% expressed OPCML mRNA, while 85% of normal ovarian tissue and 76.5% of benign ovarian tumor. The ratio of expression of OPCML mRNA in ovarian epithelial carcinoma was significantly lower than those of normal (chi2 = 30.108, P = 0.0000) and benign tumors (chi2 = 21.162, P = 0.000). No OPCML mRNA expression was found in SKOV-3 and CAOV3, but was found in 3AO. Methylations were detected in 44.4% of cancer cells promoter, while 0% in normal ovarian tissue and benign ovarian tumors. The ratio of methylation of ovarian epithelial carcinoma was significantly higher than those of normal (chi2 = 13.630, P = 0.0000) and benign tumors (chi2 = 11.797, P = 0.000). Methylation was found in SKOV-3 and CAOV3, but not in 3AO. The relationship between gene expression and promoter methylation was correlated (r = 11.589, P = 0.002), especially at Hap I1 site (r = 11.640, P = 0.004). Methylation was also found in SKOV-3 and CAOV3 cell lines, but not in 3AO cell line.

CONCLUSIONDeletion of OPCML gene exists in ovarian epithelial carcinoma cell. The gene promoter methylations, especially Hap II motif, may be one of pathways that contribute the inhibition of OPCML expression.

Adult ; Aged ; Cell Adhesion Molecules ; genetics ; Cell Line, Tumor ; CpG Islands ; genetics ; DNA Methylation ; Female ; GPI-Linked Proteins ; Gene Deletion ; Humans ; Middle Aged ; Ovarian Neoplasms ; genetics ; pathology ; Promoter Regions, Genetic ; genetics ; RNA, Messenger ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo study the expressions of VEGF/VEGFRs and activation of STATs in ovarian epithelial carcinoma, and to elucidate direct effect of VEGF on ovarian carcinoma cells.

METHODSTissue samples from 42 women with primary ovarian epithelial carcinoma (OVCA), 29 with begnin ovarian tumor (OVBT) and 11 with normal ovarian tissue (NOV) were collected. LSAB immunohistochemical staining was used to determine the expression of VEGF, VEGFR1, VEGFR2 and activated STATS (P-STAT1, P-STAT3, P-STAT5, P-STAT6) proteins.

RESULTS(1) Semi-quantitative scoring showed that VEGF expression in OVCA was significantly higher than that in OVBT and NOV (P < 0.01). Expressions of VEGFR1 and VEGFR2 were significantly elevated in OVCA, including tumor cells and stromal vascular endothelial cells (P < 0.01, compared with OVBT and NOV). There was no difference in VEGFRs expressions between OVBT and NOV. (2) In OVCA, tumor cells and endothelial cells expressed P-STAT3 and P-STAT5 at significantly higher levels than those in OVBT and NOV (P = 0.000). The staining of P-STAT1 and P-STAT6 was weak with no significant differences among OVCA, OVBT and NOV. (3) Expressions of VEGFR1 and VEGFR2 in endothelial cells were significantly correlated with P-STAT5 and P-STAT3, respectively (P = 0.006 and 0.001). In cancer cells, VEGF, VEGFR1 and VEGFR2 were all significantly correlated with P-STAT3 and P-STAT5 (P = 0.000), but not with P-STAT1 or P-STAT6.

CONCLUSIONVEGF affects ovarian carcinoma cells via VEGFRs, and STATs probably participate in intracellular signaling of VEGF.

Adult ; Aged ; Cystadenocarcinoma, Mucinous ; metabolism ; pathology ; Cystadenocarcinoma, Serous ; metabolism ; pathology ; Cystadenoma, Mucinous ; metabolism ; pathology ; Cystadenoma, Serous ; metabolism ; pathology ; DNA-Binding Proteins ; metabolism ; Endothelial Cells ; metabolism ; Female ; Humans ; Middle Aged ; Milk Proteins ; metabolism ; Ovarian Neoplasms ; metabolism ; pathology ; Ovary ; metabolism ; STAT3 Transcription Factor ; STAT5 Transcription Factor ; Signal Transduction ; Trans-Activators ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism ; Vascular Endothelial Growth Factor Receptor-1 ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

Objective To establish a real time PCR assay with a novel fluorescence quencher for identification of mutation of clarithromycin -resistance gene of Helicobacter pylori.Methods Two mutations of 23S rDNA gene in Helicobacter pylori,No.2142 and 2143,were chosen as targets for detection,and then the primers and the probe with a novel fluorescence quencher were designed.The genome DNA of Helicobacter pylori was extracted,and then detected by real time PCR reported here.Meanwhile,the specificity,reproducibility and sensitivity of the assay were evaluated.Finally,the real time PCR described here,the real time PCR based on TaqMan,and a sequencing assay were applied to detect 55 Helicobacter pylori strains isolated from clinical specimens,respectively.The results from three assays were compared with each other in order to further evaluate the applicability of this assay in clinic.Results It indicated that the mutation points related to clarithromycin -resistance,A2142G and A2143G,were identified by real time PCR with a novel fluorescence quencher rapidly and accurately.Moreover the coefficient of variation was less than 5%.The limit of detection was 100 copies/reaction.While this assay was applied directly to detect 55 Helicobacter pylori strains,the results were in accordance with those obtained from a TaqMan real time PCR and a sequencing assay,respectively.Conclusion The real time PCR described here was a simple,reliable and accurate approach and substituted for the TaqMan real time PCR for identification of two mutation points of clarithromycin -resistance,A2142G and A2143G in Helicobacter pylori.Thus,a novel tool for diagnosis of gene mutation was provided and the results might be regarded as a substantial evidence for clinical individual therapy.