Design, synthesis and evaluation of phenoxyacetic acid-based PTP1B inhibitors / 药学学报

Protein tyrosine phosphatase (PTP) 1B is a potential therapeutic target for type 2 diabetes. Phosphotyrosine (pTyr) mimetics still dominate the currently available PTP1B inhibitors. The phenoxyacetic acid moiety was taken as a pTyr mimetic herein and phenoxyacetic acid-based compounds 2a-2g and 3a-3c were designed. Among them, compounds 2a-2g exhibited potent inhibition against PTP1B, and compound 2g showed an IC50 of 0.42 μmol·L-1 against PTP1B. Compound 2f exhibited pharmacological profiles similar to that of rosiglitazone, and could improve the insulin sensitivity and the serum total cholesterol level. The results suggest that PTP1B inhibitors might be effective in treating type 2 diabetes as well as associated metabolic syndromes.

An approach to estimate the characterizations of mmulti-detector CT / 中国医学装备

Objective: The purpose of the current study was to investigate the correction coefficient of the characterizations of multi-detector CT (MDCT). Methods: The dose profile of Siemens SOMATOM Definition Flash CT scanner was measured with CT-SD 16 detector under the conditions of different collimations, pitches and tube voltages in phantoms of different diameters, and the ratio between weighted CTDI∞and weighted CTDI100 was calculated. Results:The ratio between weighted CTDI∞and weighted CTDI100, which is growing for increasing beam collimation, was found to range from 1.123 to 1.162 in head phantom and range from 1.118 to 1.173 in body phantom. Conclusion: For MDCT, the use of CTDI100, which is one of the most commonly used characterizations of CT, has always underestimated the levels of radiation dose. Therefore, CTDI100 should be corrected.

A method to correct the characterizations of MDCT / 中国医学装备

Objective:To correct the characterizations of MDCT radiation dose by exploring the relationship between CTDIw,∞ and CTDIw.Methods: CTDI100 and CTDI∞ were measured under the conditions of different collimations, pitches and tube voltages of Siemens Definition Flash CT, and CTDIw and CTDIw,∞ were calculated.Results: There were significant differences between CTDIw and CTDIw,∞ which were measured at 0.05 level. And there were no significant differences between CTDIw,∞ after corrected and CTDIw,∞ which were measured at 0.05 level.Conclusion:The characterizations of MDCT which were commonly used were not accurate enough. The result after correction were very closed to the real CTDIw,∞. This showed that the method to correct CTDIw of Siemens Definition Flash CT was mostly accurate. And methods to correct CTDIw of other MDCT needed to be further studied.

Design, synthesis and evaluation of malonic acid-based PTP1B inhibitors / 药学学报

Protein tyrosine phosphatase (PTP) 1B is a potential target for the treatment of diabetes and obesity. Phosphotyrosine (pTyr) is the substrate for PTP1B dephosphorylation. Malonic acid moiety was used herein as a mimic of the phosphate group in pTyr, and novel malonic acid derivatives 1-7 were designed, synthesized and evaluated as PTP1B inhibitors. Results from enzymatic assays indicated that compounds 3 and 4 exhibited potent inhibition against human recombinant PTP1B with IC50 values of 7.66 and 1.88 micromol x L(-1), respectively.

PTEN tumor suppressor gene combined with doxycycline inhibites telomerase activity in human mucoepidermoid carcinoma cell line / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of PTEN tumor suppressor gene combined with doxycycline on telomerase activity in human mucoepidermoid carcinoma cell line.</p><p><b>METHODS</b>The wild-type PTEN tumor suppressor gene or empty vector was introduced into mucoepidermoid carcinoma cell line in vitro, then the cancer cells were treated with doxycycline. Cancer cell survival was determined by MTT assay. Telomerase activity was determined using telomerase repeat amplification protocol-enzyme-linked immunosorbent assay (TRAP-ELISA).</p><p><b>RESULTS</b>Compared to the control cells, cancer cells transfected with the wild-type PTEN gene showed growth inhibition and increased sensitivity to doxycycyline, and the ratio of augment of drug sensitivity was 1.65-4.75. The telomerase activity in cancer cells treared with PTEN gene transfection or doxycycline alone decreased, however, telomerase activity in combined group decreased more remarkably.</p><p><b>CONCLUSION</b>PTEN gene in combination with doxycycline has significant inhibitory effect on telomerase activity in cancer cells.</p>

The inhibition of fragile histidine triad gene on the proliferation and tumorigenicity of mucoepidermoid carcinoma cells / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the suppression effect of exogenous fragile histidine triad (FHIT) gene on biological property of MEC-1 cells.</p><p><b>METHODS</b>In order to study the FHIT function in MEC-1 cells, wild-type FHIT gene was transferred into mucoepidermoid carcinoma MEC-1 cells. The proliferation and kinetics, cell cycle, clonal forming rate, and apoptosis of MEC-1 cells, before and after FHIT gene transfection in vitro, and tumor loci formed on mice after injection of transferred MEC-1 cells in vivo were observed by immunochemical staining, flow cytometry analysis, and so on.</p><p><b>RESULTS</b>It can be seen that exogenous FHIT gene transfer could significantly inhibit the proliferation and reduce the kinetics of MEC-1 cells in vitro, prolong DT from (21.03+/-0.41) h to (26.86+/-0.71) h, and also keep less cells in cell cycle phase S, whilst more cells in phase G1, Additionally, the exogenous FHIT was found to be able to remarkably suppress MEC-1 cells of forming tumor loci in nude mice by lessen tumor weight, and promote higher differentiation of MEC-1 cells to be mucous cells.</p><p><b>CONCLUSION</b>Exogenous FHIT gene could suppress the proliferation, tumorigenicity and improve the differentiation of MEC-1 cells, in vitro and in vivo.</p>

Genome sequencing and analysis of foot-and-mouth disease virus Asia1/YNBS/58 strain / 病毒学报

The full-length genomic sequence of foot-and-mouth disease virus (FMDV) Asia1/YNBS/58 strain was determined by RT-PCR and compared with other 17 reference strains. The results showed that the complete genome of Asia1/YNBS/58 was 8164nt long including a 1061-nt 5' untranslated region (UTR), a 6990-nt open reading frame (ORF), and a 113-nt 3'UTR. The homology analysis indicated that the UTR regions and non-structural proteins were more conserved than the structural proteins in FMDV. VP1 exhibited the lowest conservation and VP4 was exceptionally conserved. The VP1-, VP2-, and VP3-based phylogenetic trees were divided into distinct clusters according to different serotypes, while the other gene-based phylogenetic trees exhibited some degree of intercross among serotypes. This study is the first description of the full-length genomic sequence of FMDV Chinese serotype Asia1.

Establishment of indirect ELISA diagnose based on the VP1 structural protein of foot-and-mouth disease virus (FMDV) in pigs / 生物工程学报

The complete gene encoding the structural protein of FMDV(VP1) was subcloned into expression vector pPROex-HT, resulting in the fusion expression plasmid pPROexHT-VP1. After transformed into E. coli BL21(DE3) and induced by IPTG, the fusion protein was expressed in high level. Western blot was performed to confirm that the expressed fusion protein could specifically react with antiserum against FMDV. Based on the fusion protein further purified, a novel indirect ELISA (VP1-ELISA) was developed to detect FMDV antibody in pigs. Comparison between VPl-ELISA and the government standard kit (liquid phase block ELISA) showed the two methods had 96.25 percent agreement by detecting 80 serum samples, indicating that the indirect VP1-ELISA was specific and sensitive.

Molecular cloning and characteristics of cDNA encoding pig beta6 subunit for FMDV receptor / 生物工程学报

In order to study the roles of integrin beta6 in Foot-and-Mouth Disease Virus infection, pig integrin beta6 was firstly molecularly cloned from RNA of the tongue and lung of recovered pig infected experimentally with foot-and-mouth-disease virus (FMDV), and was compared with the beta6 gene of other animals available in GenBank at nucleotide and amino acid leves. GeneBank association number of the beta6 gene is EF432729. Pig integrin beta6 gene (2367bp) encodes a polypeptide of 788 amino acids consisting of 9 potential N-linked glycosylation sites, 3 Glycosaminoglycan attachment sites, a cGMP-dependent protein kinase phosphorylation site, 10 Protein kinase C phosphorylation sites, 2 EGF-like domains and 2 cysteine-rich regions. Pig integrin beta6 subunit has a 26-residue putative signal peptide, a 681-residue ectodomain, a 29-residue transmembrane domain, and a 52-residue cytoplasmic domain. 11 mutant nucleotides were found in beta6 gene coding region and 9 amino acids were changed. The nucleotide sequence similarity of integrin beta6 gene between rheses monkey, mouse, Norway rat, dog, guinea pig, human, bovine, sheep is 79.5%, 84.9%, 85.4%, 85.2%, 88.7%, 90.1%, 91.9% and 91.9%, and the amino acid sequence similarity is 93.5%, 88.2%, 88.5%, 88.3%, 91.0%, 92.8%, 93.3% and 93.4% respectively. This study will lay a foundation for understanding the interactions of FMDV with receptors.

Cloning and sequence analysis of cDNA encoding porcine alphav subunit for FMDV receptor / 生物工程学报

Receptors play a crucial role in determining the pathogenesis and tissue tropism of virus. Foot-and-mouth disease virus (FMDV) has been showed to use four integrins, alphavbeta1, alphavbeta3, alphavbeta6 and alphavbeta8 as receptors to initiate infection. In this study, the porcine integrin alphav gene was cloned by RT-PCR from the lung tissue of healed pig infected experimently with FMDV, and compared its nucleotide and deduced amino acid sequence with the av gene of other animals. The 3141bp cDNA of bovine integrin alphav encodes a polypeptide of 1046 amino acids consisting of a 30-residue putative signal peptide, a 955-residue ectodomain, a 29-residue transmembrane domain, and a 32-residue cytoplasmic domain. The ectodomain contains 11 potential N-linked glycosylation sites (NXT/NXS), 2 calcium binding domains (DX[D/N] XDGXXD) and 18 cysteine residues. The nucleotide sequence similarities of integrin alphav between pig and cattle, human, rheses monkey, house mouse, chicken, dog are 93.3%, 91.5%, 91.4%, 85.6%, 73.2% and 89.9% respectively; and the amino acid sequence similarities are 96.3%, 94.6%, 94.1%, 90.8%, 81.6% and 93.8%, respectively. The alphav gene of cattle and pig exhibited the highest sequence homology. It is possible that host tropism of FMDV may related to divergence in receptors among different species.

Construction of eukaryotic expression vector of short hairpin RNA for transforming growth factor-beta1 / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To construct the plasmid containing short hairpin RNA (shRNA) of TGF-beta1 expression vector.</p><p><b>METHODS</b>Short chain oligonucleotide was designed according to the TGF-beta1 mRNA sequence provided by Genebank, then DNA segment was gained through annealing after chemosynthesis, and then was cloned to pWH1 vector. The recombinant TGF-beta1 shRNA expression vector was evaluated by using enzyme cutting. At last, the constructed TGF-beta1 expression vector was transfected into salivary gland mucoepidermoid carcinoma (Ms) cells by Lipofectomine TM 2000, and its effect on TGF-beta1 expression was observed by RT-PCR and immunohistochemistry.</p><p><b>RESULTS</b>Successful construction was identified by enzyme cutting and the constructed plasmid was called pWH1-TGF-beta1. The shRNA and it inhibited the TGF-beta1 mRNA and protein expression effectively.</p><p><b>CONCLUSION</b>The constructed TGF-beta1 shRNA expression vector can block the TGF-beta1 expression in salivary gland mucoepidermoid carcinoma cells.</p>

Screening and identification of metastasis-related gene expression in tongue carcinoma with cDNA microarray assay / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To identify metastasis-associated genes in tongue carcinoma and to better understand the mechanism underlying tongue carcinoma metastasis. To compared mRNA expression profiles of two tongue carcinoma cell strains with high and low metastatic potentials using microarray technology.</p><p><b>METHODS</b>Tca8113 and Tb cells were used as model systems to study the molecular mechanism of tumor metastasis. Two fluorescent cDNA probes labeled with Cy3 and Cy5 dyes were prepared from the mRNA samples of Tca8113 and Tb cells by reverse transcription method. The two color probes were then mixed and hybridized to the cDNA chip constructed by double dots of 1 152 human genes, and scanned at two wave lengths. Differential expression genes from the above two cell lines were analyzed using computer. Then six of the different expression genes were further validated by RT-PCR technique.</p><p><b>RESULTS</b>In the 1 152 clones of known genes and expressed sequence tags that were analyzed, 37 showed significantly different (minimum 2 folds) expression levels in two cell lines. Among the 37 genes, 15 were up regulated (with ratio more than 2) and 22 down regulated (with ratio less than 1/2). The results of RT-PCR analysis were coincident with those of microarray assay.</p><p><b>CONCLUSION</b>Some of these genes are known to be involved in human tumor antigen, immune surveillance, adhesion, cell signaling pathway and growth control. It is suggested that the microarray in combination with a relevant analysis facilitates rapid and simultaneous identification of multiple genes of interests and in this study it provided a profound clue to screen candidate targets for early diagnosis and intervention.</p>

Nucleic Acid Sequence-Based Amplification and Its Applications in Viral Diagnosis / 中国生物工程杂志

Nucleic acid sequence-based amplification(NASBA) is a sensitive,isothermal,transcription-based amplification system specifically designed for the detection of RNA targets,which could amplify templete RNA in 2h under isothermal condition at about 42?C and without any special equipment.NASBA is now widely applicated in diagnosis of many pathogenic microorganism.It is mainly about principles and applications of NASBA in viral diagnosis.

Molecular Characteristics of cDNA Encoding Bactrian Camel ?6 Subunit for FMDV Receptor / 中国生物工程杂志

Receptors play a crucial role in determining the host specificity and tissue tropism of virus. Foot-and-mouth disease virus(FMDV)has been showed to use four integrins, ?v?1, ?v?3, ?v?6 and ?v?8 as receptors to initiate infection and ?v?6 functions as the major receptor.The cDNA encoding bactrian camel integrin ?6 from the lung tissue was cloned and sequenced. The 2367bp cDNA of bactrian camel integrin ?6 encodes a polypeptide of 788 amino acids consisting of a 26-residue putative signal peptide, a 681-residue ectodomain with 8 potential N-linked glycosylation sites and 58 cysteine residues, a 29-residue transmembrane domain, and a 52-residue cytoplasmic domain with a NPLY motif and 1 potential N-linked glycosylation site. The nucleotide sequence similarity of integrin ?6 between bactrian camel and cattle, pig, sheep, human, mouse, Norway rat is 91.1%、91.8%、90.6%、90.5%、83.7%、84.1%, and the amino acid sequence similarity is 94.3%、93.4%、93.4%、93.7%、88.7%、88.6%, respectively. The bactrian camel ?6 gene exhibited the higher sequence homology with the ?6 gene of cattle, pig and sheep, indicating their close genetic relationships. It is possible that host tropism of FMDV may related to divergence in ?6 receptors among different species.

Effects of 17 beta-estradiol on the adhesion, invasion and motility potential of salivary mucoepidermoid carcinoma Mc3 cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the effects of 17 beta-estradiol on the adhesion, invasion and motility potential of salivary mucoepidermoid carcinoma Mc3 cells.</p><p><b>METHODS</b>The effects of 17 beta-estradiol on adhesion, invasion and motility potential of salivary mucoepidermoid carcinoma Mc3 cells were investigated with cell attachment assay on fibronectin (FN), wound assay, chemotaxis assay, and gelatin-incorporated SDS-PAGE electrophoresis. The expression of estrogen receptor in Mc3 cells was determined by immunohistochemistry assay.</p><p><b>RESULTS</b>Attachment rates of Mc3 cells treated with E2 at 10(-9), 10(-8), 10(-7), 10(-6) mol/L were 38.3%, 50.4%, 69.2% and 91.1% respectively, and the rate in control was 25.0%. When exposed to 17 beta-estradiol at 10(-9), 10(-8), 10(-7) and 10(-6) mol/L for 48 h, motility of Mc3 cells on FN increased by 16.9%, 40.9%, 36.4% and 38.8% respectively. When at 10(-6) mol/l, 17 beta-estradiol increased chemotaxis potential of Mc3 cells to FN by 60.3%. The activity of 68 000 matrix metalloproteinase (MMP-2) of Mc3 cells was enhanced at different levels by 10(-9), 10(-8), 10(-7), 10(-6) mol/L of 17 beta-estradiol, and estrogen receptor was also detected in nucleus of Mc3 cells by immunohistochemistry assay.</p><p><b>CONCLUSIONS</b>17 beta-estradiol at physiological concentration may enhance the adhesion, invasion and motility potential of salivary mucoepidermoid carcinoma Mc3 cells.</p>

Improvement of osseointegration of titanium dental implants by a modified sandblasted surface / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study effects of the modified sandblasted surface of titanium implants, developed by authors, on the bone healing process.</p><p><b>METHODS</b>Osteoblasts were derived from the 5th passage of human fetal osteoblasts after primary isolation. Alkaline phosphatase (ALP) activities and protein contents of cellular layers, and osteocalcin contents in culturing medium were employed as criteria to evaluate osteogenic functions and differentiation of osteoblasts. The ALP activity was assayed utilizing the kinetic method, the protein content utilizing the Coomassie's method, and the osteocalcin content utilizing the radioimmune assay (RIA) method. Values of all criteria were divided by the corresponding cell numbers of different groups at a respective time point for the purpose of standardization. Samples were assigned to three groups-the modified sandblasted surface group, the smooth surface group and the blank control group, The culture was ended at, 4 days and 13 days.</p><p><b>RESULTS</b>At 4 days of culture, the modified sandblasted surface group showed a superiority to the smooth group with respects to the ALP activity [(17.390 +/- 1.595) nmol PNP x min(-1) x 10(-6) cells vs. (10.978 +/- 1.879) nmol PNP x min(-1) x 10(-6) cells] and protein content [(152.7 +/- 16.3) micro g/10(6) cells vs. (58.0 +/- 5.9) micro g/10(6) cells] of cellular layers and the osteocalcincontent [(43.0 +/- 6.1) ng/10(6) cells vs. (24.9 +/- 6.0) ng/10(6) cells] in culturing medium. Till the 13th day of culture, no differences were detected.</p><p><b>CONCLUSIONS</b>It is cytologically proved that the modified sandblasted surface can accelerate the bone healing process of implants though the improvement of osteoblastic functions and differentiation.</p>

Survey on patient dose in cardiac intervention / 介入放射学杂志

Objective To collect information of patient doses of interventional radiology in Beijing Xuanwu Hospital,and investigate correlation between the peak skin dose(PSD) and dose-area product(DAP).Methods Radiation doses from 135 patients have been studied including 84 coronary angiographies(CAG) and 51 percutaneous transluminal coronary angioplasties(PCI).Dose-area product(DAP) values,cumulative dose(CD) at interventional reference points,fluoroscopy times,total number of cine frames were collected for each patient.Skin dose measurements were made with thermoluminescent dosimeters(TLD) placed as a 10 ? 9 arrays of TLDs on the body.The grid of TLDs arrays was 5 ? 4 cm.Results Mean values for dose-area product were 2690.84 ?Gym2 for CAG and 7946.91 ?Gym2 for PCI.Mean values for CD were 431.6 mGy cm2 for CAG and 1395.3 mGy for PCI.Mean fluoroscopy times were 2.9 min for CAG and 10.9 min for PCI and mean number of frames were 544 and 945 for CAG and PCI,respectively.PSD values ranged from 26.18 to 120.37 mGy for CAG and 38.91 to 184.79 mGy for PCI.The relationship between DAP and PSD was r = 0.52 for CAG and r = 0.54 for PCI.The correlation of PSD with CD was r = 0.45 for CAG and r = 0.53 for PCI.Conclusion Comparison shows that patients DAP,CD and fluoroscopy time values were comparable with other publications.Skin dose values of investigated patients are below the threshold dose for radiation skin injury(2 Gy).There is no good relationship between DAP and PSD.So calculation of individual maximum skin dose based on DAP data is not reliable and needs to find a new reference value for skin dose.(J Intervent Radiol,2007,16:222-225)

Heparan Sulfate and Foot-and-mouth Disease Virus Infection / 微生物学通报

Receptors are primary determinant of viral tropism and disease pathogenesis.Heparan sulfates (HS)are ubiquitous,polyanionic carbohydrate chains linked to core proteins in cell membranes and ex- tracellular matrices of all eukaryotes.HS have also been demonstrated to function as receptors or co-receptors for a number of different viruses.To date,HS and four RGD-dependent integrins,?v?3,?v?6, ?v?1,and?v?8 have been reported to serve as receptors for Foot-and-mouth disease virus(FMDV).Different receptors may be used to interact with host cells during FMDV infection.Studies on the structure and function of receptors are very important for understanding the interaction between host cells and FMDV. Here,We mainly reviews the progress on the biological characteristics of HS and its roles in FMDV infection.

Integrin and Foot-and-mouth Disease Virus Infection / 微生物学通报

Integrins are a family of cell surface glycoproteins that contribute to a variety of biological functions, including cell growth, migration, proliferation and morphology. In addition, integrins also play the important roles in pathological process. Several viruses have been showed to use integrins as receptors or co-receptors to infect host cells.This article mainly reviews the progress on integrins and their roles in FMDV infection.