A novel gene,located between dnrX and drrB in the genome of daunorubicin-producing strain Streptomyces coeruleorubidus SIPI-1482,was cloned and named as dauW.The full sequence of dauW was submitted to GenBank(Accession No.EF523565).Blast result indicated that it showed high homology with dnrW in GenBank.The exact function of dauW is as yet unknown despite the possibility that it might belong to a family of FAD-dependent oxidoreductases on the basis of conserved domain analysis.dauW was cloned into expression plasmids pET-28a(+)and pET-32a(+),respectively,and was successfully expressed in E.coli DE3 after induction with IPTG.The preliminary results of the expression of dauW suggested that it might be involved in the self resistance in Streptomyces coeruleorubidus due to the increased resistance to daunorubicin in the E.coli host.

TDP-4-ketohexulose reductase, encoded by dnmV, is important in daunorubicin biosynthesis. To obtain a daunorubicin block mutant, double cross-over plasmid pYG817 was constructed by inserting apramycin resistant gene and amplified dnmV together with upstream dnmU into vector pUC18. dnmV was successfully disrupted after transformation of daunorubicin-producing strain SIPI-1482 by pYG817. Daunorubicin was absent from metabolites of the resulting transformant, and its biosynthesis can be reconstituted by introducing dnmV expression plasmid into the disruptant, although the yield is lower than wild-type SIPI-1482, according to HPLC analysis. This mutant can be a good candidate for production of anthracycline such as epi-daunorubicin by introducing exogenous gene into the host.

To improve the growth enhancement activity of Vitreoscilla hemoglobin(VHb), Vitreoscilla hemoglobin gene(vgb) was mutated by error-prone PCR and then reconstituted by DNA shuffling. The shuffling library was constructed by inserting the shuffled genes into the downstream of vgb natural promoter and transforming them into E.coli DH5?. Mutated active VHb proteins were first screened in test tubes according to host cell pellets color and then in shake flasks according to host pellets wet weight .One active mutant protein, VHb′042506, was obtained after second screening. It could increased the host wet weight by 31.25% and 58.75% than that of the control which bearing natural VHb under microaerobic and extremely microaerobic conditions, respectively. Sequencing and alignment results showed that 11 nucleotides were mutated, thus resulted in 4 amino acids changes occurred in this mutant protein. CO difference spectrum test also indicated that it had higher specific absorption.

TTI gene coding for Tsetse thrombin inhibitor was modified with E.coli bias codon and expressed in Escherichia coli with high efficiency.Recombinant protein was purified to more than 98% purity.Assay for enzyme activity determination was set up.The result showed that the fusion protein exhibited inhibiting activity for thrombin.Inhibitory rate of purified TTI was 73% when concentration of thrombin and substrate was 10U/ml and 250?mol/L respectively.Inhibition pattern was determined as competitive with Ki at 35?mol/L.

?-lactamase inhibitor research is popular for its potential on ?-lactam antibiotics resistant strain.A ?-lactamase binding peptide SIPIS04-01 was obtained by the yeast two-hybid system.In vitro assay showed that it can inhibit the ?-lactamase activity.In order to improve the expression level of the recombinant peptide,a two-copy expression plasmid pYG563 was constructed by random orientation tandem repeat method after codon modification,the two-copy plasmid was successfully expressed and the product was increased by 48.4% than that of one-copy plasmid.Purified peptide showed inhibitory activity against TEM-1 ?-lactamase in vitro and the inhhibitory constant Ki was measured.

Objective To explore the value of 18F-FDG PET/CT on the assessment of chemotherapy response in patients with diffuse large B-cell lymphoma (DLBCL). Methods 18F-FDG PET/CT was performed before and after 4 cycles of chemotherapy( R-CHOP or CHOP protocol) in 53 patients with DLBCL. The patients were divided into 3 groups: complete response group, partial response group and no response group. The therapeutic response was assessed by comparing post-treatment 18F-FDG PET/CT with pre-treatment PET/CT. Complete remission (CR) rate at the end of chemotherapy was calculated. χ2 test was performed with software SPSS 13.0. Results CR rates of complete response group, partially response group and no response group were 88.5% (23/26), 73.3% (11/15) and 8.3% (1/12), respectively (χ2=23.548, P=0.000). CR rates of the complete and partially response groups were significantly higher than those of no response group (χ2=22.656, P=0.000; χ2=11.407, P=0.001). Conclusion 18F-FDG PET/CT may be useful for the assessment of chemotherapy response in DLBCL.

Canrenone is an important intermediate for the synthesis of eplerenone,a cardiovascular drug.C_ 11 ?-hydroxylation of canrenone is the key reaction,which can be done by microbial transformation.Rhizopus sp.SIPI-0602,kept in our lab,could high selectively transform canrenone to a compound named SIPI-11.By determining and analyzing the MS,UV,NMR etc.spectra of compound SIPI-11,its chemical structure was elucidated to be 11?-hydroxycanrenone.The study on flask transformation technology showed that the transformation ratio exceeded 90% when the substrate concentration was not more than 6g/L.

OBJECTIVETo investigate the rule of lymph-node metastasis in gastric cardia cancer and the rational extent of lymph node dissection.

METHODSClinicopathological data of 77 patients with gastric cardia cancer were reviewed and the relationship between extent of lymph-node dissection and prognosis was analyzed retrospectively.

RESULTS(1) The lymph node metastasis rates were 64.9% for N(1), 14.3% for N(2) and 10.4% for N(3). (2) No lymph node metastasis was detected in T(1) stage tumor and maximum diameter of less than 2.0 cm. The lymph node metastasis rates were 20% for T(2), 68.2% for T(3) and 82.8% for T(4) respectively. (3) Lymph node No.1, 3, 2 were often involved in the metastasis of lymph node group 1, and No.7, 8, 10, 9 in Group 2. In lymph node group 3, lymph node metastasis rates were 6.5% for No.5, 1.3% for No.6, 1.3% for No.16 and 2.6% for No.107-110. (4) The five-year survival rates were 36.5% for D(3), 31.3% for D(2), and 22.7% for D(1) lymphadenectomy respectively. The survival rates of patients undergone D(2) and D(3) lymphadenectomy were significantly higher than that undergone D(1) dissection (P<0.05).

CONCLUSIOND(2) or more than D(2) lymphadenectomy associated with enlargement of esophageal hiatus via laparotomy, lower partial esophagectomy and total gastrectomy is able to achieve surgical resectability and improve the survival rate of gastric cardia cancer patients.

Cardia ; Female ; Humans ; Lymph Node Excision ; Lymph Nodes ; pathology ; surgery ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Retrospective Studies ; Stomach Neoplasms ; pathology ; surgery

OBJECTIVETo establish the rat model of acute spinal cord injury, followed by aprimary study on this model with ¹H NMR based on metabonomics and to explore the metabonomics and biomarkers of spinal cord injury rat.

METHODSTwenty eight-week-old adult male SD rats of clean grade, with body weight of (200±10) g, were divided into sham operation group and model group in accordance with the law of random numbers, and every group had 10 rats. The rats of sham operation group were operated without damaging the spinal cord, and rats of model group were made an animal model of spinal cord incomplete injury according to the modified Allen's method. According to BBB score to observate the motor function of rats on the 1th, 5th, and 7th days after surgery. Postoperative spinal cord tissue was collected in order to pathologic observation at the 7th day, and the metabolic profilings of serum and spinal cord from spinal cord injury rats were studied by ¹H NMR spectroscopy.

RESULTSThe hindlimb motion of rats did not obviously change in sham operation group, there was no significant difference at each time point;and rats of model group occurred flaccid paralysis of both lower extremities, there was a significant difference at each time; there was significant differences between two groups at each time. Pathological results showed the spinal cord structure was normal with uniform innervation in shame group, while in model group, the spinal cord structure was mussy, and the neurons were decreased, with inflammatory cells and necrotic tissue. Analysis of metabonomics showed that concentration of very low density fat protein (VLDL), low density fat protein (LDL), glutamine, citric acid, dimethylglycine (DMG) in the serum and glutathione, 3-OH-butyrate, N-Acetyl-L-aspartic acid (NAA), glycerophosphocholine (GPC), glutamic acid, and ascorbate in spinal cord had significant changes(<0.05).

CONCLUSIONSThere are significant differences in metabolic profile from serum and spinal cord sample between model group and sham operation group, it conduces to explain the changes of small molecular substances in serum and spinal cord tissue after spinal cord injury, this provides the research basis for targeted research on the role of metabolic markers in patients with acute spinal cord injury.

AIMStudies on synthesis and antibacterial activity of new heterocycles.

METHODSThe cyclocondensation of [(3-pyridyl)-1,3,4-oxadiazol-2-yl] thio acetic acid with various aroyl hydrazines in the presence of POCl3 and xylene gave the corresponding titled compounds, and the in vitro antibacterial activity was primarily evaluated by the method of cupplate diffusion solution.

RESULTSSixteen novel titled compounds were synthesized, their structures were confirmed by IR, 1HNMR, MS and elemental analysis. Biological screening results demonstrated that most of the compounds prepared displayed potential antibacterial activity.

CONCLUSIONOxadiazoles incorporting pyridyl oxadiazole ring may be usefully antibacterial candidate drugs.

Anti-Bacterial Agents ; chemical synthesis ; chemistry ; pharmacology ; Escherichia coli ; drug effects ; Oxadiazoles ; chemical synthesis ; chemistry ; pharmacology ; Proteus vulgaris ; drug effects ; Staphylococcus aureus ; drug effects