The determination and clinical application of inosine 5'-monophosphate dehydrogenase activity / 药学学报

Inosine 5'-monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme in de novo biosynthesis of guanine and plays an important role in cell proliferation. In clinic, IMPDH inhibitors are mainly used in fields of anticancer, antiviral, anti-parasitic, and immunosuppressive chemotherapy. However, since there are usually great inter-and intra-individual variability between drug concentration and clinical effect of IMPDH inhibitors, the enzyme activity of IMPDH may be applied as a specific biomarker and combined with the pharmacokinetics (PK) monitoring to improve efficacy and safety of IMPDH inhibitors. This review aims to discuss the assay of IMPDH activity measurement and its clinical application in recent years and provide valuable insights and theoretical basis for the development of IMPDH inhibitors' pharmacodynamics monitoring.

CYP3A4 genetic polymorphisms predict cyclosporine-related clinical events in Chinese renal transplant recipients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cyclosporin A (CsA) is a substrate of both cytochrome P450 3A (CYP3A) and P-glycoprotein (P-gp), some of the single nucleotide polymorphisms (SNPs) in these genes are associated with interindividual variations in CsA pharmacokinetics. We studied the influence of these SNPs on the incidence of rejection and CsA nephrotoxicity, as well as pneumonia within one year after renal transplant and post-transplantation diabetes mellitus (PTDM), in order to find whether genetic evaluation may help to identify patients at risk and to modulate CsA therapy to optimize graft and patient outcomes.</p><p><b>METHODS</b>A total of 208 renal transplant recipients receiving CsA were genotyped for ABCB1 (C1236T, G2677T/A, and C3435T), CYP3A4 1G, and CYP3A5 3 by direct sequencing method. Retrospective case control study was utilized to identify the association between CYP3A4 1G, CYP3A5 3, ABCB1 genetic polymorphisms and CsA-related outcomes.</p><p><b>RESULTS</b>The patients with a CYP3A4 1G/ 1G genotype were found to have a higher incidence of acute rejection compared with those with CYP3A4 1/1.</p><p><b>CONCLUSION</b>CYP3A4 1G/1G genotype predict increased risk of acute rejection, so genetic evaluation may partly help to identify patients at risk and to modulate CsA therapy to optimize graft and patient outcomes.</p>

Over expression of hyperplasia suppressor gene inhibits the malignant phenotype of breast cancer cell / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of over expression of human hyperplasia suppressor gene (HSG) on proliferation, invasion, apoptosis and cell cycle of human breast cancer cells and to determine the relationship between HSG and Ras-dependent signaling pathway.</p><p><b>METHODS</b>Full length HSG coding sequences were cloned into plasmid pcDNA3.0. The recombinant plasmids were transfected into MDA-MB-231, a highly malignant breast cancer cell line. Vacant pcDNA3.0 was used as the control. MTT, Matrigel transwell assay and flow cytometric analysis were used to test for proliferation, invasion, cell cycle distribution and apoptosis of tumor cells after transient transfection of HSG.GST-pulldown and Western blotting assays were performed to investigate the activity of Ras protein.</p><p><b>RESULTS</b>HSG transfection inhibited proliferation of MDA-MB-231 cells, and significantly decreased the number of invading cells in Matrigel transwell assay compared with the vector/231 group (78.5 +/- 5.8 vs. 131.1 +/- 14.5) cells. FACS analyses demonstrated that compared with the vector/231 group, up-regulation of HSG promoted breast cancer cell apoptosis [(35.8 +/- 4.8)% vs. (25.6 +/- 3.5%)] and induced G(0)/G(1) phase arrest [(56.3 +/- 2.3)% vs. (50.4 +/- 1.9%)] after transfection for 18 hours. Furthermore, GST-pulldown assay showed that over-expression of HSG remarkably decreased the activity of Ras (about 65% lower than control).</p><p><b>CONCLUSIONS</b>HSG exibits multiple anticancer functions in breast cancer cells including inhibition of proliferation and in vitro invasion, G(0)/G(1) arrest and promotion of apoptosis. Besides, inhibition of Ras-dependent signaling pathway may be involved in these processes.</p>

Immunoglobulin expression in colon cancer cell line HT-29 and its biological activities / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To determine the expression of immunoglobulins in HT-29 cells (an established colon cancer cell line, and explore their effect on the biological activities of the cancer cells.)</p><p><b>METHODS</b>The transcripts of variable regions of immunoglobulin heavy chains in HT-29 cells were detected by RT-PCR. Antisense CDR3 (specific to HT-29)-pIRES 1 neo vector was constructed, then transfected into HT-29 cells by electroporation. Programmed cell death and growth inhibition of HT-29 cells were detected by FCM and MTT, respectively.</p><p><b>RESULTS</b>The transcripts of Ig heavy chain (V(H) CDR3 region) were expressed in HT-29 cells. Moreover, they showed a monoclonal characteristic after being sequenced. After transfection of the antisense vector of CDR3 (specific to HT-29)-pIRES 1 neo, expression level of Ig in HT-29 cells was significantly decreased, and growth inhibition (P < 0.05) and apoptosis (P < 0.01) were induced.</p><p><b>CONCLUSION</b>These results suggest that tumor derived Ig could promote the survival and growth of tumor cells.</p>

Antimicrobial susceptibility of 487 Mycoplasma strains / 中国感染与化疗杂志

Objective To analyze the antimicrobial susceptibility of Mycoplasma isolates for rational antimicrobial therapy. Methods BioM?rieux IST kit was used for identification and susceptibility testing of Mycoplasma strains.Results Mycoplasma was positive in 49.5% of the specimens tested.Of the Mycoplasma detected,Ureaplasma urealyticum(Uu)alone accounted for 74.7%,Mycoplasma huminis(Mh)alone accounted for 18.1%,and Uu+Mh was identified in 7.2% of the patients.The results of antimicrobial susceptibility testing showed that the Mycoplasma isolates were most susceptible to doxycycline (98.1%).Ciprofloxacin was the least active (17.3%).Conclusions Doxyeycline,josamycin,and clarithromycin can be used in the treatment of urinary tract infections caused by Mycoplasma.

The protein X4 of severe acute respiratory syndrome-associated coronavirus is expressed on both virus-infected cells and lung tissue of severe acute respiratory syndrome patients and inhibits growth of Balb/c 3T3 cell line / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The genome of the severe acute respiratory syndrome-associated coronavirus (SARS-CoV) includes sequences encoding the putative protein X4 (ORF8, ORF7a), consisting of 122 amino acids. The deduced sequence contains a probable cleaved signal peptide sequence and a C-terminal transmembrane helix, indicating that protein X4 is likely to be a type I membrane protein. This study was conducted to demonstrate whether the protein X4 was expressed and its essential function in the process of SARS-CoV infection.</p><p><b>METHODS</b>The prokaryotic and eukaryotic protein X4-expressing plasmids were constructed. Recombinant soluble protein X4 was purified from E. coli using ion exchange chromatography, and the preparation was injected into chicken for rising specific polyclonal antibodies. The expression of protein X4 in SARS-CoV-infected Vero E6 cells and lung tissues from patients with SARS was performed using immunofluorescence assay and immunohistochemistry technique. The preliminary function of protein X4 was evaluated by treatment with and over-expression of protein X4 in cell lines. Western blot was employed to evaluate the expression of protein X4 in SARS-CoV particles.</p><p><b>RESULTS</b>We expressed and purified soluble recombinant protein X4 from E.coli, and generated specific antibodies against protein X4. Western blot proved that the protein X4 was not assembled in the SARS-CoV particles. Indirect immunofluorescence assays revealed that the expression of protein X4 was detected at 8 hours after infection in SARS-CoV-infected Vero E6 cells. It was also detected in the lung tissues from patients with SARS. Treatment with and overexpression of protein X4 inhibited the growth of Balb/c 3T3 cells as determined by cell counting and MTT assays.</p><p><b>CONCLUSION</b>The results provide the evidence of protein X4 expression following SARS-CoV infection, and may facilitate further investigation of the immunopathological mechanism of SARS.</p>

Preparation, identification, and analysis on tissue chips of polyclonal anti-peptide antibody to chemokine-like factor 1 / 中国医学科学院学报

<p><b>OBJECTIVE</b>To prepare the polyclonal anti-peptide antibody against chemokine-like factor1 (CKLF1) and apply it to the expression and functional studies of CKLF1.</p><p><b>METHODS</b>CKLF1 was analyzed with bioinformatics methods. The 16 amino acids sequence peptide was selected from CKLF1 C terminal end. Antibody was raised by immunizing rabbits with the peptide conjugated to keyhole limpet hemocyanin (KLH).</p><p><b>RESULTS</b>A high titer polycolonal antibody was obtained from the rabbit against the peptide. ELISA analysis proved that the titer of rabbit serum against anti-peptide of CKLF1 was up to 10(-4). Western blot analysis revealed that it could react not only with recombinant CKLF1 expressed in a cell-Free Protein Biosynthesis System and Drosophila S2 cells, but also recognize the endogenous CKLFs in the tissue array. Positive staining was detected in the normal bronchial cartilage, gastric mucosa, and gastric smooth muscle tissues. Normal rectum and well-differentiated rectal carcinoma showed strong positive staining, but the poor-differentiated rectal carcinoma samples revealed negative staining.</p><p><b>CONCLUSION</b>The anti-peptide antibody can specifically recognize CKLFs and may be a useful reagent for the detection of CKLF1.</p>