Therapeutic effect of anti-CXCL1 neutralizing antibody on acute ulcerative colitis in mice / 中南大学学报(医学版)

Objective:To evaluate the therapeutic effect of CXCL1 monoclonal antibody on dextra sulfate sodium (DSS)-induced acute ulcerative colitis (UC) in mice,and to elucidate its effect on the expressions ofTNF-α,IFN-γ,,IL-17 and IL-10 as well as neutrophil infiltration.Methods:Female BALB/c mice were randomly divided into a normal group (DSS-),a disease group (DSS+saline),an anti-CXCL1 antibody group (DSS+anti-CXCL1 Ab) and a treatment control group (DSS+IgG Ab).The DSS+saline,DSS+anti-CXCL1 Ab and DSS+anti-CXCL1 Ab groups were given 3.5％ DSS solution as drinking water to induce acute intestinal inflammation,while the normal control was given distilled water freely.The DSS+anti-CXCL1 Ab mice were intraperitoneal injected with anti-CXCL1 Ab (4 mg/kg) on the 3rd and 6th day.Same amount of rat IgG Ab was given in the DSS+IgG Ab group.The normal group and the disease group were injected with 0.9％ sodium chloride solution.The value of disease activity index (DAI) and the injury of colorectal tissue were measured.The levels of TNF-α,IFN-γ,IL-10 and IL-17 in colonic tissues of mice were detected by RT-PCR.Myeloperoxidase (MPO),a specific marker of neutrophils was measured by immunohistochemistry.Results:Compared with the normal control group,DAI score and colorectal injury score in the disease group were significantly increased,but the DAI and colorectal in the mice with acute ulcerative colitis tissue damage score were significantly reduced after anti-CXCL1 Ab intervention.Compared with the normal control group,mRNA levels of TNF-α,IFN-γ and IL-17 in the colorectal tissues were significantly elevated (P＜0.05) in the disease group while the IL-10 was decreased;these effects were attenuated by anti-CXCL1 Ab intervention (P＜0.05).Immunohistochemistry showed that the infiltration of neutrophils (MPO+) in the colon tissue was significantly increased in the disease group,while the anti-CXCL1 Ab treatment could significantly reduce the neutrophil infiltration in colon tissue (P＜0.05).Conclusion:Anti-CXCL1 Ab relieves the progression of DSS-induced acute ulcerative colitis by suppressing proinflammatory expression and neutrophil infiltration.

Construction of bromodomain-deleted BRD7 mutation vector based on homologous recombination and reverse PCR amplification / 中南大学学报(医学版)

OBJECTIVE@#To construct a eukaryotic expression vector of bromodomain-containing protein 7 (BRD7) with deletion of bromodomain (BRD7△brd) using the homologous recombination and reverse PCR amplification techniques.@*METHODS@#The linear DNA fragments of bromodomain-deleted mutation of BRD7 (pIRES2-EGFP- 3Flag/BRD7△brd) were amplified by one pair of reverse PCR primers using high-fidelity enzyme, and then these fragments were transformed into E.coli to obtain the eukaryotic expression vector expressing BRD7△brd protein based on homologous recombination and plasmid cyclization.@*RESULTS@#Bromodomain-deleted clones were identified by digestion with restrictive enzymes, and then the sequence and protein expression were further confirmed by sequencing and Western blot assays. The results suggest that pIRES2-EGFP-3Flag/BRD7△brd was successfully constructed.@*CONCLUSION@#We establish a simple and quick method to construct plasmids with pIRES2-EGFP- 3Flag/BRD7△brd using reverse PCR amplification and homologous recombination techniques. We also found that the concentration of template in PCR reaction system is one of the critical factors that affect the rate of homologous recombination. Of all, this improved technique could be widely used in the construction of gene mutations.

Association between serum levels of S100A8/S100A9 and clinical features of colorectal cancer patients / 中南大学学报(医学版)

OBJECTIVE@#To analyze the association between serum levels of S100A8/S100A9 and clinicopathological features of colorectal cancer patients.
@*METHODS@#A total of 82 patients with CRC and 14 healthy controls were enrolled for this study. The levels of S100A8 and S100A9 in serum were detected by ELISA assay. The association between S100A8/S100A9 and clinicopathological features was analyzed by student-t test and one-way ANOVA. Receiver Operating Characteristic curve was used to analyze diagnostic efficiency of serum S100A8 and S100A9 for colon rectal cancer. Logistic regression model was also established to analyze the possible risk factors for elevation of S100A8/S100A9.
@*RESULTS@#The levels of S100A8 and S100A9 were (1 403.3±593.7) and (2 890.3±994.9) pg/mL in patients with colon cancer, and (712.8±265.3) and (1 492.7±564.6) pg/mL in controls, respectively, with significant difference between the two groups (P<0.01). The similar results were found in rectal cancer patients, with a level of S100A8 and S100A9 at (1 417.7±666.5) and (3 026.7±887.6) pg/mL, respectively. Diagnostic sensitivity and specificity of S100A8 and S100A9 are better than traditional biomarkers. The levels of S100A9 in serum of CRC patients were correlated with clinical stages and distant metastasis. Serum levels of S100A9 in patients of stage III [(3 111.9±178.5) pg/mL] and stage IV [(3 831.4±278.5) pg/mL] were significantly (P<0.01) higher than that in stage I [(2 276.1±167.4) pg/mL], whereas there was significant change in S100A8 levels. Logistic regression showed the possible risk factors for the elevation of S100A9, including depth of invasion, lymphatic metastasis and degree of differentiation (P<0.05).
@*CONCLUSION@#Serum level of S100A8 and S100A9 in CRC patients were significantly increased and serum level of S100A9 was positively correlated with the malignant features of CRC.

Toll-like receptors and non-resolving inflammation-related cancer / 中南大学学报(医学版)

Toll-like receptors (TLRs) is a type of pattern recognition receptors (PRRs), which are singular, non-catalytic and highly homologous. TLRs not only play significant roles in natural immunity, but also act as a bridge between innate immunity and adaptive immunity. Recent studies have revealed that TLRs play critical roles in the development of non-resolving inflammation-related cancer,including the formation of tumor microenvironment, invasion and metastasis, immune escape, etc. Further investigation into the mechanisms responsible for the function of TLRs will be of great value in tumor prevention, early diagnosis and therapy.

Study on the clinical practice teaching of respiratory medicine / 中华医学教育探索杂志

After years of respiratory medicine clinical practice teaching , we have discovered that there exist some problems such as teachers' job burnout, teachers' lowprofessional knowledge level of clinical teaching and lack of teaching ability, medical students' fear, low self-esteem, psycho-logi-cal fear and emotional weariness breeding as well as the patients and their family members ' refusal of practice because of their worrying about being a test and so on. To solve these problems , we have put forward some proposals such as recognizing and rewarding teachers to affirm their teaching levels , organizing teachers to participate in academic conferences, seminars, etc. to expand their professional knowledge in order to improve their overall quality. And at the same time, we have adopted PBL teaching method, applied multimedia technology and network platforms, put emphasis on basic skills training, the improvementof departmental rotation assessment, the establishment of teaching files and doctor-patient communication and other ways to improve clinical teaching quality and develop interns' clinical thinking ability to help them transitto clinicians.

T-SPOT.TB in the diagnosis of tuberculous peritonitis / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the value of T-SPOT.TB in the diagnosis of tuberculous peritonitis (TBP).@*METHODS@#A total of 50 patients with clinically suspected TBP admitted from August 2011 to July 2012 from the Third Xiangya Hospital were enrolled in this prospective cohort study. Peripheral blood T-SPOT.TB, purified protein derivatives of tuberculin (PPD) skin test, serum tuberculosis antibody (TB-Ab) and ascitic adenosine deaminase (ADA) were measured in the 50 patients and we compared the diagnostic value of the 4 methods.@*RESULTS@#According to the standard of diagnosis of TBP and grouping, 24 patients were diagnosed with TBP, 17 non-TBP and 9 undiagnosed in the end. The sensitivity of T-SPOT.TB for the diagnosis of TBP was 91.7% (22/24), with statistical significance when compared with PPD skin test 37.5% (9/24), serum TB-Ab 16.7% (4/24), and ascitic ADA 36.4% (8/22) (P0.05). The positive prediction value of T-SPOT.TB for the diagnosis of TBP was 84.6% (22/26), without statistical significance when compared with PPD skin test 75.0% (9/12), serum TB-Ab 57.1% (4/7), and ascitic ADA 100%(8/8) (P>0.05). The negative prediction value of T-SPOT.TB for the identification of non-TBP was 86.7% (13/15), with statistical significance when compared with PPD skin test 31.8% (7/22), serum TB-Ab 35.5% (11/31), and ascitic ADA 50.0% (14/28) (P<0.05).@*CONCLUSION@#Peripheral blood T-SPOT.TB for the diagnosis of TBP is highly sensitive, which is better than PPD skin test, serum TB-Ab, and ascitic ADA. T-SPOT.TB has an important reference for diagnosing suspected TBP quickly and accurately.

MicroRNAs and nonresolving inflammation-related cancer / 中南大学学报(医学版)

The link between nonresolving inflammation and cancer is well documented. On the one hand, epidemiologic evidence supports that approximately 25% of all human cancer worldwide is caused by nonresolving inflammation. On the other hand, inflammatory cells are found in the microenvironment of most, if not all, tumors. In the tumor micro-environment, inflammatory cells and molecules influence almost every aspect of cancer. MicroRNAs (miRNAs) participate in the initiation and progression of nonresolving inflammation-related cancer by regulating the key genes and related signaling pathways. Further investigation into the molecular mechanisms by which miRNAs carry out their functions will be of great value in the prevention, early diagnosis, and treatment of tumors.

miR-126 inhibits colon cancer proliferation and invasion through targeting IRS1, SLC7A5 and TOM1 gene / 中南大学学报(医学版)

Objective:To explore the expression pattern and function of miR-126 in human colon cancer and the underlying mechanisms. Methods:hTe expression pattern of miR-126 in high-density human colon cancer tissue microarray was analyzed by in situ hybridization. Further more, the biological function of miR-126 in colon cancer in vitro was investigated by establishing a stable miR-126 over-expression cell lines. Result:hTe expression of miR-126 was lower in the tumor tissue, especially in metastasis tissue. hTe down-regulation of miR-126 was more obvious in the patients who displayed bad prognosis (P=0.025). Over-expression of miR-126 in colon cancer cell was able to inhibit cell proliferation, promote cell apoptosis and reduce the invasive ability. MiR-126 significantly enhanced the sensitivity of the colon cancer cell to chemotherapeutic drug. It has been shown that IRS1, SLC75A and TOM1 were the potential target genes of miR-126 in colon cancer. Conclusion:MiR-126 was able to inhibit the development of colon cancer and its level was closely related with the prognosis of patients with colon cancer. The potential target genes for miR-126 might include IRS1, SLC7A5 and TOM1. Therefore, miR-126 might be a therapeutic target for colon cancer diagnosis and treatment.

Effect of macrophages on ulcerative colitis-associated carcinogenesis / 中南大学学报(医学版)

Ulcerative colitis is a non-specific colorectal inflammation of unknown causes. It is now known to complicate the dangers of colorectal cancer more than was previously thought. Macrophages are an important part of immune system and play a positive role in immune reaction. But it has been shown that the phenotype and the function of macrophages change in the tumor microenvironment. Through their interaction with colorectal cancer cells and by releasing large quantities of cytokines, macrophages promote colorectal cancer cells by inhibiting angiogenesis and inhibit apoptosis. But the macrophages are also affected by cancer, interact with other inflammatory cells, and become immune suppressed. Thus the changes of macrophages are inseparable with colitis-associated colorectal carcinogenesis.

Transcriptomic regulation and molecular mechanism of polygenic tumor at different stages / 中南大学学报(医学版)

The research team on the National Key Scientific Program of China: "Transcriptomic regulation and molecular mechanism research of polygenic tumor at different stages" has focused on the field of transcriptomics of 4 common polygenic tumors, including nasopharyngeal carcinoma(NPC), breast cancer, colorectal cancer, and glioma. Extensive laboratory work has been carried out on the expression and regulation of tumor transcriptomics; identification of tumor suppressor/susceptible genes; mechanism of tumor epigenetics including miRNAs, and comparative study of specific gene/protein cluster of tumor transcriptomics and proteomics. Genes including SPLUNC1, LTF, BRD7, NOR1, BRCA1/2, PALB2, AF1Q, SOX17, NGX6, SOX7, and LRRC4 have been identified as the key transcriptional regulation genes during the stage of tumor initiation and invasion. Accordingly,the NPC gene signal regulation network of "SPLUNC1-miR-141-target genes", the breast cancer interaction signal pathway of "miR-193b-uPA",the glioma signal network of "miR-381- LRRC4-MEK/ERK/AKT", and the miRNA-target gene network of colorectal cancer metastasis related gene NGX6 have been thoroughly elucidated. These fruitful Results imply that the changes of key molecules in crucial signal pathway will cause severe dysfunction in signal transduction and gene regulation network in polygenic tumors, indicating that in the category of pathogenesis,these tumors may further classify as the "Disease of gene signal transduction and gene regulation network disorder". The researches have laid solid foundation for revealing the molecular mechanism and transcriptomic regulation of polygenic tumors at different stages.

Definition and function identification of nucleus export signal of BRD7 / 中南大学学报(医学版)

OBJECTIVE@#To localize and define the region of nucleus export signal (NES) on BRD7, and determine the role of this region in nucleus export of the external protein.@*METHODS@#Based on an in vitro expressed model of green fluorescence protein (GFP), we performed DNA walking analysis to set BRD7 into several sections according to the structural characteristics of BRD7, investigated the effect of different sections of BRD7 on nucleus export of GFP, defined the region of nucleus export signal sequence of BRD7, and further ascertained the content of amino acids in BRD7 and potential localization of BRD7 NES by bioinformatics.@*RESULTS@#B7C1 fragments ranged from aa219 to aa450 in BRD7 were found to target the external protein GFP into the cytoplasm detected by GFP direct fluorescence, which could be inhibited by NES inhibitor Leptomycin B (LMB). This region was rich in hydrophobic amino acid residues but no typical NES with characteristics of leucine-rich sequence by bioinformatics.@*CONCLUSION@#The region from aa219 to aa450 is primarily defined as an atypical NES in BRD7.

Inflammatory factors promote the development of colorectal cancer / 中南大学学报(医学版)

OBJECTIVE@#To study the change of inflammatory factors at different stages of colorectal cancer (CRC).@*METHODS@#Thirty normal subjects, 30 patients with colorectal adenomatous polyps and 120 CRC patients at different stages were enrolled. IgG, IgM, and IgA levels, the inflammatory cytokines IL-2, 4, 6, 10, and 12 and the expression of TGF-β 1 and VEGF in the serum were analyzed by ELISA or immunoturbidimetry.@*RESULTS@#The serum concentrations of IL-12, TGF-β 1, and IL-6 in the CRC patients were statistically different compared with the normal and adenomatous polyps, and increased as the disease progressed (P0.05). The serum level of IgG, IgM, and IgA in the 3 groups showed no significant difference (P>0.05).@*CONCLUSION@#The serum level of inflammatory cytokines TGF-β 1, IL-6, and IL-12 increases gradually with the development of CRC, which may change the microcirculation of patients with CRC, and promote the development of CRC.

Mycophenolate mofetil combined with low dose prednisone in the treatment for adults with minimal change nephrotic syndrome and concomitant HBsAg positive / 中华肾脏病杂志

Objective To assess the safety and efficacy of mycophenolate mofetil (MMF) combined with low dose corticosteroid in the treatment of adults with minimal change nephrotic syndrome and concomitant HBsAg positive (MCNS-HBsAg). Methods Thirty adults with MCNS-HBsAg were enrolled in this prospective study and were assigned to two groups. The MMF group (n=14) received low dose of prednisone combined with MMF (MMF 1.0 to 2.0 g/d patients of Pred group versus 35.7% patients of MMF group. 43.8% patients of Pred group versus 21.4% patients of MMF group received lamivudine therapy. Elevation of alanine aminotransferase(ALT) ocurred in 50% patients of Pred group and 28.6% patients of MMF group. The complete remission (CR) rate after 24 weeks treatment was 11/14 in Pred group versus 10/12 in MMF group. 6/11 patients of the Pred group and 4/10 patients of the MMF group who achieved CR experienced relapses during follow-up. Conclusions Use of MMF combined with low dose prednisone is as effective as conventional prednisone regimen in treating adults with MCNS-HBsAg. The MMF protocol seems to be superior in HBV reactivation to conventional prednisone protocol.