1.Infections in systemic lupus erythematosus:risk factors,clinical characteristics and early diagnosis
Chinese Journal of Practical Internal Medicine 2001;0(02):-
Infectious diseases have emerged as one of the leading causes of morbidity and mortality in systemic lupus erythematosus(SLE)patients,so early diagnosis of infectious complication in SLE patients is absolutely beneficial for patients' prognosis.C-reactive protein(CRP)and Procalcitonin(PCT)can help to differentiate infections with active SLE in SLE patients.Serum KL-6 can help to distinguish pulmonary involvement of SLE from infections in SLE patient.The most common pathogens for infection in SLE patients are bacteria,but more attention should be paid to viral and fungal infections,which have been on a rise recently.
2.Metabolic engineering of Escherichia coli for thymidine production.
Simeng LI ; Xiaojing LI ; Tao CHEN
Chinese Journal of Biotechnology 2015;31(1):105-114
Thymidine is a commercially useful precursor for production of antiviral compounds such as stavudine and azidothymidine. Biosynthesis of thymidine by Escherichia coli BL21 (DE3) was studied using metabolic engineering methods. The deoA, tdk and udp of the salvage pathway were disrupted from E. coli BL21 to construct BS03 that produced 21.6 mg thymidine per liter. Additional deletion of pgi and pyrL increased the supply of thymidine precursors and the resulting strain BS05 produced 90.5 mg thymidine/L. At last, ushA, thyA, dut, ndk, nrdA and nrdB of thymidine biosynthetic pathway were overexpressed, and the resulting strain BS08 produced 272 mg thymidine/L. In fed-batch fermentation, BS08 accumulated 1248.8 mg thymidine/L. Metabolically engineered strain E. coli has potential applications for thymidine production.
Biosynthetic Pathways
;
Escherichia coli
;
genetics
;
metabolism
;
Fermentation
;
Industrial Microbiology
;
Metabolic Engineering
;
Thymidine
;
biosynthesis
3.Effect of recombinant human granulocyte colony-stimulating factor on Nogo receptor expression in the brain tissues of neonatal rats after hypoxic-ischemic brain damage
Rong CHEN ; Xiaojing ZHANG ; Zhixu HE
Chinese Journal of Applied Clinical Pediatrics 2015;30(6):456-460
Objective To observe-the different effects of 2 doses recombinant human granulocyte colony-stimulating factors (rhG-CSF) on Nogo receptor(NgR) expression in the brain tissue of neonatal rats after hypoxic-ischemic brain damage(HIBD) at different times in order to reveal the neuroprotective effects of rhG-CSF.Methods Seven-day neonatal Sprague-Dawley(SD) rats were randomly divided into 4 groups by drawing method:sham operation group,model group,low-dose rhG-CSF group and high-dose rhG-CSF group,24 rats in each group.Then each group was divided into 4 subgroups (6 rats in each subgroup)and all rats were exterminated at different times after HIBD(1 d,3 d,7 d and 14 d).In the low-dose rhG-CSF group and high-dose rhG-CSF group,the rats were given daily doses of rhG-CSF 50 μg/kg,100 μg/kg respectively for 7 days by subcutaneous injection immediately after the molding(total 7 injections).In model group,rats received an injection of same amount of 9 g/L saline.In sham operation group,rats received no special treatment.Brain tissues of rats from each group were collected at different time points.The expressions of NgR protein and NgR mRNA in the left brain tissue were detected by immunohistochemistry and real-time fluorescent quantitative polymerase chain reaction (PCR).Results Immunohistochemistry:NgR proteins were constitutively expressed in the cerebral cortex in sham operation group at each time point;compared with sham operation group,the expressions of NgR in model group were increased markedly at each time point (135.67 ± 16.63,173.98 ± 17.82,234.00 ± 14.70,319.59 ± 25.22),and the differences were statistically significant(all P < 0.01);compared with model group,the expressions of NgR in the cerebral cortex in low-dose rhG-CSF group (134.35 ± 8.89,109.04 ± 12.62,75.99 ± 13.39) and high-dose rhG-CSF group (81.38 ± 12.25,80.14 ± 10.50,72.58 ± 13.66) on the 3rd,7th,14th day were reduced significantly (all P < 0.01).Compared with low-dose rhG-CSF group,the protein expressions of NgR in the high-does rhG-CSF group were decreased faster,and had the marked difference on the 3rd,7th day (P < 0.05).Real-time fluorescent quantitative PCR:compared with the sham operation group,the expressions of NgR mRNA increased gradually in the cerebral cortex in the model group (1.34 ± 0.24,1.88 ± 0.27,2.88 ± 0.84,4.26 ± 0.86),the differences in NgR mRNA expression were statistically significant at different times(all P < 0.05) ; compared with model group,the expressions of NgR mRNA in low-dose rhG-CSF group on the 7th (1.08 ± 0.30),14th day (0.93 ± O.26) and high-dose rhG-CSF group on the 3rd (0.61 ± 0.10),7th (0.56 ± 0.28),14th day (0.47 ± 0.12) were significantly different (all P < 0.05).The expressions of low-dose group and high-dose group were reduced gradually.The NgR mRNA expression reduced more quickly in the high-dose group than in the low-dose rhG-CSF group and had substantial difference between two groups in 3 days (P < 0.05).Conclusions The findings suggest that rhG-CSF intervention can reduce the expressions of NgR in the brain tissues of neonatal rats after HIBD,and low-dose rhG-CSF also has neuroprotective effect,but it could be weaker than high-dose rhG-CSF.
4.Research progress of microRNAs in colorectal cancer therapy
Xiaojing LIN ; Jingjing XU ; Yan CHEN
Journal of International Oncology 2015;(5):388-391
The molecular targeted therapy method using microRNAs(miRNAs)is gradually stepping into people′s vision. miRNAs affect colorectal cancer progress via abnormal expression in tumor cells or micro-environment. The high or low expressions of miRNAs in specific tissues probably have an impact on the expressions of oncogenes,tumor suppressor genes or other aspects including the surrounding environments,the metastases and the drug tolerance of tumors,thus contributing to curing the colorectal cancer. Nowadays, miRNA has entered the stage of animal experiments.
5.Meta-analysis on the relationship between MTHFR gene polymorphisms and colorectal cancer
Xiaojing YU ; Kun CHEN ; Mingjuan JIN
Chinese Journal of Prevention and Control of Chronic Diseases 2006;0(02):-
Objective To evaluate the relationship between 5,10-Methylenetetrahydrofolate reductase(MTHFR) gene polymorphisms and colorectal cancer(CRC).Methods Studies were selected based on the criteria for inclusion.The Meta-analysis software,REVMAN 4.2,was applied for checking the heterogeneity across the studies and calculating the pooled OR.The results were evaluated by the analyses of publication bias and sensitivity.Results A total of 9 787 cases and 12 986 controls from 18 studies for C677T and a total of 4 422 cases and 5 819 controls from 9 studies for A1 298C were included.No heterogeneity among the studies was found.For codon 677,the frequencies of CC,CT and TT genotypes were 46.48%,43.81% and 9.71% in cases,and 45.03%,43.08% and 11.89% in controls,respectively.The pooled OR of TT vs.CT+CC was 0.80(95%CI 0.74~0.87).For codon 1 298,the frequencies of AA,AC and CC genotypes were 53.60%,39.39% and 7.01% in cases,and 53.31%,38.67% and 8.03% in controls,respectively.The pooled OR of CC vs.AC+AA was 0.84(95%CI 0.72~0.97).Conclusions MTHFR 677TT is at lower risk of developing CRC and 1 298CC genotypes might be associated with the decreased risk of developing CRC.
6.Effects of arachidonic acid on action potential and L-type calcium current in rabbit cardiomyocytes
Chengyun LIU ; Guiqing CHEN ; Xiaojing GENG
Chinese Journal of Pathophysiology 1999;0(09):-
AIM: To study the influence of arachidonic acid(AA) on the action potential and L-type calcium current in rabbit cardiomyocytes.METHODS: Single ventricular myocyte was isolated using enzyme dispersion method.Whole-cell clamp-patch technique was used to record action potential and L-type calcium current.RESULTS: ① AA shortened action potential duration obviously,without marked effect on the resting potential and action potential amplitude.② AA reduced the current densities from(10.21?3.15)PA/PF to(6.53?2.17)PA/PF(n=6,P
7.Study on Transdermal Penetration of Loratadine Inclusion Complexes Gels in Vitro
Ying HU ; Xinshu CHEN ; Xiaojing XIA
China Pharmacy 2007;0(29):-
0.05).The value of J of negative group was(6.180?0.214) ?g?cm-2?h-1,while there was significant difference between trial group and negative group(P
8.Construction of recombinant lentiviral vector and interfering carrier for tumor necrosis factor alpha stimulated gene 6 and its effect on proliferation and apoptosis of human keloid fibroblasts
Zhao CHEN ; Xiaojing LI ; Hui WANG
Chinese Journal of Tissue Engineering Research 2016;20(29):4319-4327
BACKGROUND:Current research has shown that tumor necrosis factorαstimulated gene 6 (TSG-6) has anti-inflammatory effect, and the scar formation can be inhibited by local injection of TSG-6 protein at the early stage of trauma. However, the mechanism of this effect is stil unclear. OBJECTIVE:To construct the lentiviral expression vector and shRNA vector for human TSG-6, with stable overexpression, transfection and interference, and to explore the effect of TSG-6 on proliferation and apoptosis of keloid fibroblast cel lines. METHODS:Human keloid fibroblast cel s were isolated from the keloid’s tissue by enzyme digestion and identified by immunocytochemistry assay. Lentiviral vectors pLVX-puro-TSG-6 and pLVX-shRNA1-TSG-6 were constructed and transfected into human keloid fibroblast, exclusively. Expression levels of TSG-6 mRNA and protein were detected by RT-PCR and western blot assay. MTT assay and flow cytometry were used to estimate the cel proliferation and apoptosis in each group after transfection. In addition, expression of Bcl-2, p53 and active-caspase-3 were detected by western blot assay in each group. RESULTS AND CONCLUSION:(1) Human keloid fibroblasts were separated successful y. Under the light microscope, cel s were spindle. Immunohistochemical staining for vimentin was performed in the fifth passage of cel s, with the positive rate of 100%. Cel s were negative for cytokeratin. (2) Recombinant lentiviral vectors and stably transfected cel lines were successful y established. TSG-6 gene expression was altered apparently. Compared with the control group, cel proliferation was delayed and apoptotic rate was noticeably increased in TSG-6 gene overexpression group. Cel proliferation increased and apoptotic rate decreased in the TSG-6 gene intervention group (P<0.05). (3) Western blot assay results demonstrated that Bcl-2 expression reduced, P53 and Active-caspase-3 expression significantly increased in the TSG-6 gene overexpression group (P<0.05). (4) These finding showed that TSG-6 could inhibit proliferation and induce apoptosis in keloid fibroblasts. Its mechanism may be associated with the down-regulation of Bcl-2 protein expression, up-regulation of P53 protein expression and increased Caspase-3 activity.
9.An investigation of the necessity on performing preoperative trachea and esophageal pushing in cervical operation using anterior approach
Yixiu CHEN ; Xiaojing SU ; Ziming YAO
Chinese Journal of Practical Nursing 2015;31(27):2046-2049
Objective To investigate the influence of preoperative training of pushing trachea and esophagus or not on cervical operation by anterior approach.Methods All patients were randomly divided into two groups:experimental group and control group (56 cases,respectively).Patients in the former group had no training of pushing trachea and esophagus,while patients in the latter group had,recording the data of surgery duration,operator's degree of satisfaction,blood loss,blood pressure,heart rate,and oxygen saturation during operation,hospital stay and cost.Meanwhile,we observed and compared the VAS scores and the complication rate etc.between two groups.Results There were no differences between two groups in surgery duration,operator's degree of satisfaction,blood loss,blood pressure,heart rate,and oxygen saturation during operation,hospital stay and cost,nor in the VAS scores and the throat-related complications rate.The hospital stay and cost of patients in experimental group were longer and higher than that of patients in control group,(7.3±1.6) d vs (5.8±1.4) d,(48 468.3±4 313.8) vs (45 228.4±4 124.6) yuan,t=5.280,4.062,P<0.05.Conclusions Training of pushing trachea and esophagus has no influence in the throat-related complications rate,VAS scores and operator's degree of satisfaction.Instead,training of pushing trachea and esophagus increases hospital stay and cost and amount of nurse's work.So,it's not necessary to undertake the preoperative training before cervical operation by anterior.
10.Determination of Complanatuside in Semen Astragali Complanati and Its Processed Products by HPLC
Cheng HE ; Xiaojing TANG ; Yuwu CHEN
Chinese Journal of Information on Traditional Chinese Medicine 2006;0(03):-
Objective To establish a method for the determination of complanatuside in Semen Astragali Complanati, and study the content change of complanatuside processed. Method HPLC was used with Apollo-C18 column (4.6 mm?250 mm, 5 ?m), acetonitrile-0.1%phosphoric acid (21∶79) as mobile phase, the flow rate at 1.0 mL/min, and detected wavelength was set at 266 nm. Result Complanatuside showed a good linearity relationship in the range of 0.041 6~0.665 6 ?g, r =0.999 9. The average recovery was 100.6%, RSD was 0.73%. Conclusion The method is simple, accurate, reproducibility and strong specificity. It can be used for the quality control of Semen Astragali Complanati. Processing with salt can lead to content decrease of complanatuside in Semen Astragali Complanati.