The enzyme catalytic reaction properties of H2O2-4-aminoantipyrine (4-AAP)-the different chlorophenolic derivatives color systems using hemoglobin as enzyme mimetic of peroxidase was studied. Meanwhile, the relationship of structure-effect for the different chlorophenolic derivatives as substrate has been discussed, and the mechanism of catalytic reaction has also been investigated. The method for the determination of hydrogen peroxide was proposed using 4-AAP-2,3,4-trichlorophenol system with hemoglobin as catalyst. The sensitivity of method proposed for the determination of H2O2 was better than other similar systems. The apparent molar absorptivity of the chromogenic reaction for H2O2 was 2.21×104 L*mol-1*cm-1. Satisfied results were obtained in the determination of H2O2 in synthetic samples by this method. Also, the method was coupled with glucose oxidation reaction for the determination of glucose in human serum.

A 27-year-old woman who suffered from a 2-year history of systemic lupus erythematosus (SLE) presented with a 6-month history of nodules and ulcer on the right lower extremity. Direct microscopic examination of the pus showed branched and septate hyphae and spores in a chain-like arrangement.Histopathological examination revealed yellowish brown hyphae and spores. Dark green velvety colony grew on Sabouraud dextrose agar (SDA). Slide culture showed branched, septate hyphae and spine-like annellated conidiophores. The isolate was identified as Exophiala spinifera by DNA sequence analysis. The strain was unable to liquefy gelatin, could grow at 25 ℃ to 39 ℃, and was sensitive to itraconazole, amphotericin B and terbinafine. Animal test revealed that the infection induced by Exophiala spinifera in immunocompromised mice was more severe than that in normal controls. Based on the clinical features, histopathological, fungal culture and DNA sequencing results, the patient was diagnosed with systemic lupus erythematosus accompanied by subcutaneous phaeohyphomycosis caused by Exophiala spinifera.

Objective To investigate the effects and mechanism of pre-treatment with an Nrf2 inducer dh404 on renal ischemia reperfusion injury in rats.Methods Thirty SD rats were divided into three groups using completely randomized digital table,dh404 was dissolved in sesame oil and was given orally 1.5 mg/kg the night before procedures and 5 hours before procedures.Rats in group Sham received no treatment of ischemic reperfusion.In group IR and group dh404,the renal ischemia reper-fusion (IR)model was established,24 hours after IR,the levels of serum creatininc (Cr)and urea ni-trogen (BUN),the activities of superoxide dismutase (SOD)and the content of malonaldehyde (MDA)in serum were measured,and hematoxylin eosin(HE)staining observe the changes in renal structure,the levels of γ-glutamate-cysteine ligase catalytic (GCLC)and modifier (GCLM)subunit, the expression of NF-κB,COX-2 and eNOS were measured.Results Compared with group Sham,the values of Cr,BUN in group IR and group dh404 were significantly higher (P <0.05).Compared to the group IR,the group dh404 Cr,BUN values significantly decreased after reperfusion for 24 h(P <0.05 ).Compared to group Sham,group IR SOD activity decreased,while the value of MDA increased(P <0.05 ).Compared to group IR,group dh404 had much higher SOD activity,while the value of MDA significantly decreased.Observed with optical microscopy,compared to group Sham, the renal tubular injury of group IR was obvious.Compared to group IR,group dh404 significantly reduced tubular injury.Compared to group IR,the levels of GCLC and modifier GCLM subunit were higher,while there were no significant differences of levels among NF-κB,COX-2 and eNOS. Conclusion Pre-treatment with an Nrf2 inducer dh404 can protect the kidney from IRI through possi-bly reducing IRI kidney oxidative stress.

13 C isotopic abundance of intracellular free amino acid with a characteristic of fast- turnover can quickly reflect changes in intracellular metabolic state. But the concentration of intracellular free amino acid is low, the existed 13 C isotope detection method based on GC-MS can not satisfy the requirement with full scan mode. In this study, the selected ion monitoring method was used to detect accuracy higher likelihood of analysis of 13 C isotopic abundance of free intracellular amino acid. First, in the full scan mode we analyzed of the fracture law of different amino acids, found the feature corresponding to each amino acid fragments, and established 16 kinds of free intracellular amino acids characteristic fragment library. Then using this characteristic fragment library, only specific m/z signal was detected in sample analysis, which realized the selected ion monitoring and improved the quality of signal. The results of amino acid standards showed that the signal-to-noise ratio, measurement precision and accuracy were improved by 17, 2. 0 and 3. 8 times compared with the full scan mode. In the analysis of coenzyme Q10 producing strains of samples, this method was successfully used to detect isotopic abundance of 8 kinds of free intracellular amino acids. This method plays an important role in the detection of 13 C isotopic abundance of the intracellular free amino acid in cell metabolism research.

Objective To evaluate the diagnosis and differentiation of solitary pulmonary nodule (SPN) using dynamic spiral CT scan of thin collimation.Methods The thin collimation no-enhanced CT scan and contrast enhanced scan in 30 seconds,1 minute,1 minutes,2 minutes,5 minutes,10 minutes,and 15 minutes after administration of media 100 ml were performed in 38 cases. Results The mean enhanced CT numbers of lung cancer and inflammatory pseudotumor were much higher than that of tuberculosis(TB) and hamartoma and statistically significant in different time of enhancement;20 HU was the threshold for a positive test,the sensitivity was 100% and the specificity was 96%.In time-attenuation curve analysis,lung cancer reached peak enhancement about 2 minutes,inflammatory pseudotumor in 5 minutes and keep longer enhanced time than that of lung cancer.No marked enhancement in SPN of TB and harmatoma,but ring-shaped enhancement can be seen in some of TB.More valuable imaging signs were found with thin collimation scan and more accurate to measure the CT numbers than traditional scan.Conclusion Dynamic spiral CT scan of thin collimation is a very valuable method for diagnosis and differentiation of SPN.

Objective To investigate the expression of RECK gene in placentas of patients with preeclampsia and its correlation with MMP-2 activation,and explore the possible roles of RECK gene in the placental trophoblast invasion mechanism.Methods RT-PCR and Western blot were used to detect the expression of RECK mRNA and protein respectively in the placental tissues of normal late pregnant women (normal pregnant group,22 cases) and pre-eclamptic patients(22 mild cases and 20 severe cases).Gelatinase zymography was used to determine MMP-2 activation ratio.Results The expression levels of RECK mRNA and protein from placenta tissues in mild,severe pre-eclamptic group were both significantly higher than those in nomal pregnant group.Moreover,the expression levels of RECK mRNA and protein in severe pre-eclamptic group were obviously increased as compared with those in mild pre-eclamptic group.There was significant difference among the three groups (all P<0.01).MMP-2 activation ratio in mild,severe pre-eclamptic group was significantly lower than that in normal pregnant group.MMP-2 activation ratio in severe pre-eclamptie groups was obviously reduced as compared with mild pre-eclamptic group.There was significant difference among the three groups(all P<0.01).The expression leVels of RECK mRNA and protein were significantly negatively correlated with MMP-2 activation ratio (both P<0.01).Conclusion The abnormal high expression of RECK and inhibition of MMP-2 activation in placentas of pre-eclamptic patients may participate in the process of placental trophoblast shallow invasion.

A method for measuring 13C isotopic abundance of intracellular metabolites of Saccharopolysporaerythraea by ultra-high performance liquid chromatography (UPLC)-triple quadrupole mass spectrometry was established.First, the chromatographic conditions of UPLC were optimized, and then the MS conditions such as unique tube lens voltage, collision energy, and ion pair were optimized.On the bases of length of the parent and daughter ions carbon chains and whether the daughter ions contain 13C atoms, the one-to-one method, one-to-many method and SIM method were established for measuring 13C isotopic abundance.Then these methods were used to measure naturally labeled intracellular metabolite standards and 13C labeled samples, and according to the gap between the experimental value and the theoretical value, the best method was established for each metabolite of different characteristics.The results showed that one-to-one method was most effective for measuring the metabolites of daughter ions not containing 13C atoms represented by sugar phosphates, one-to-many method was the best for measuring the metabolites of both parent and daughter ions containing 13C short carbon chains represented by carboxylic acids, SIM method could play a role in measuring the metabolites of both parent and daughter ions containing 13C long carbon chains represented by coenzyme A.This method had a good measurement precision and could be applied to the measurement of Saccharopolysporaerythraea intracellular metabolites, which contributed to the consequent study of metabolic mechanism and the efficient expression of erythromycin.

Objective To analyze the molecular characteristics of qnrS-positive Escherichia coli ( E. coli) strains resistant to quinolone. Methods A total of 57 qnrS1-positive clinical isolates were collect-ed from Fujian Medical University Union Hospital. Plasmid-mediated quinolone resistance ( PMQR) genes [qnrA, qnrB, qnrC, qnrD, aac(6′)-Ib-cr, qepA and oqxAB] andβ-lactamase genes (blaCTX-M-1, blaCTX-M-2, blaCTX-M-8 , blaCTX-M-9 , blaSHV and blaTEM ) were detected by PCR and then sequenced. Agar dilution method was used to analyze the antimicrobial susceptibility of the qnrS1-positive strains. Phylogenetic analysis was conducted using PCR. Multilocus sequence typing ( MLST) was performed for phenotyping. Enterobacterial repetitive intergenic consensus-polymerase chain reaction ( ERIC-PCR) was used to evaluate the genetic sim-ilarity between those isolates. Transferability of the qnrS1 genes carried by the 57 strains was examined by conjugation test with the sodiumazide-resistant E. coli J53 as the recipient strain. Mutations in the quinolone resistance-determining regions ( QRDR) in those strains were analyzed by PCR. Results All of the qnrS1-positive E. coli strains showed high resistance to quinolones. PMQR genes were harbored by 14 (24. 6％) isolates. Extended spectrum β-lactamases (ESBLs)-producing isolates accounted for 68. 4％. Mutations in the QRDR of gyrA, gyrB, parC and parE genes were found in 56 (98. 2％) strains and the most frequent point mutations were S83L (89. 5％) in gyrA gene, S80I (54. 4％) in parC gene and P415V (28. 1％) in parE gene. The qnrS1 gene was successful transferred from 13 (22. 8％) isolates to E. coli J53 by conjuga-tion. Five plasmid incompatibility groups were detected. Phylogenetic analysis showed that there were 36 (63. 2％), 13 (22. 8％), 1 (1. 8％) and 7 (12. 3％) isolates belonging to groups A, B1, B2 and D, respectively. The 57 qnrS1-positive E. coli strains were assigned to 50 ERIC types and 39 sequence types ( ST) based on the results of ERIC-PCR and MLST. Conclusions Mutations in the QRDR in E. coli strains were associated with qnrS1 gene and might play a critical role in the dissemination of quinolone-resistant bacteria.

Objective To analyze the routine test parameter levels of patients with colorectal adenoma and colorectal cancer, and develop a prediction model. Methods A total of 580 patients diagnosed with colorectal adenoma (117 patients) and colorectal cancer (463 patients) were included in the retrospective study. The patients were randomly divided into two groups according to a 7:3 ratio: a training set with 406 cases and a validation set with 174 cases. Logistic regression analysis was used to establish a prediction model, and a nomogram was drawn. The model′s discrimination, calibration, and clinical applicability were evaluated using receiver operating characteristic curve (ROC), calibration plot, and decision curve analysis (DCA). Results Univariate logistic regression analysis identified 13 potential predictors: age, fecal occult blood test (FOBT), fibrinogen (FIB), thrombin time (TT), albumin (ALB), white blood cell value (WBC), neutrophil count (NEUT#), hematocrit value (HCT), mean corpuscular hemoglobin (MCH), red cell distribution width (RDW), platelet count (PLT), mean platelet volume (MPV), and activated partial thromboplastin time (APTT). Multivariate logistic regression analysis showed MPV, FIB, ALB, FOBT, TT, and HCT were risk factors for colorectal cancer in patients with colorectal adenoma (P<0.05). A nomogram was constructed based on these predictors to build a prediction model. The AUC of the ROC curve was 0.915 for colorectal cancer in the training set and 0.836 in the validation set. Calibration plots demonstrated high prediction accuracy and good model calibration. DCA results indicated the prediction model provided greater net benefit compared with the extreme models at threshold probabilities of approximately 55%-95%. Conclusion The developed prediction model exhibits satisfactory discrimination, calibration, and clinical applicability. The model can serve as an auxiliary tool in distinguishing between colorectal adenoma and colorectal cancer in patients.

The School of Basic Medical Sciences of North Sichuan Medical University explores the reform of the basic medicine teacher's ability cultivation from the following aspects, including the classroom teaching quality, practical teaching skills, the innovation ability of scientific research, the basic and clinical integration and so on. Practice has proved that these reforms have greatly improved the quality of teachers' abilities and also the quality of education and teaching.