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Potassium dichromate titration (othophenanthroline spectrophotometry) with ammonium chloride extraction is a reliable technique to determine the high-content iron carbonate (7.5%-80%) in samples. However, the traditional methods have the disadvantages of complicated operation, large reagent consumption and analytical error. Moreover, due to the low-content iron carbonate in stream sediments, the interferences caused by other ferrous minerals easily leads to the increase of measurement error. A highly sensitive and selective method for determination of low-level iron carbonate (0.1%-6.0%) in stream sediments has been developed by Flame Atomic Absorption Spectrometry (FAAS) combined with aluminum chloride extraction in water bath and is reported in this paper. Extraction conditions were optimized so that iron carbonate in stream sediments could be completely extracted when the concentration of aluminum chloride is 100 g/L, the heating time is 60 min for water bath, and extract dosage is 80 mL. The addition of aluminum chloride with the same concentration in the standard curve can eliminate matrix interference. The detection limit of iron carbonate was 0.0015 μg/mL, the relative standard deviation (n=12) was 2.3%-4.0% and the recovery ranges from 95.0% to 107.5%. Some ferrous minerals in stream sediments such as hematite and magnetite have negligible interference on the determination of iron carbonate and the interference from pyrrhotine could be also effectively eliminated by mercuric chloride. Compared with the chemical method, the proposed method is simple and easy to operate and has high accuracy and precision.

Pseudomonas aeruginosa NJ-814, isolated from garden soil, produced an extracellular aminopeptidase that was purified using ammonium sulfate precipitation and ion exchange chromatography. The purity was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and the Mr value of the enzyme was estimated to be 55 kDa. The purified enzyme shows maximum activity at pH 9.0 and 80 °C. It exhibits high thermo-stability. Half of the activity can remain after incubation at 80 °C for 119 min. It is stable within pH range of 7.5-10.5. It is strongly activated by Co2+ and inhibited by Fe2+, Cu2+, Ni2+, Zn2+, and ethylene diamine tetraacetic acid (EDTA). The specificity of the enzyme was investigated. Within several aminoacyl- p-nitroanilines (AA- pNA), Lys- pNA is proven to be the optimal substrate. The Michaelis-Menten constant ( Km) of the enzyme for Lys- pNA and Leu- pNA were 2.32 and 9.41 mM, respectively. Peptide map fingerprinting shows that the sequence of the enzyme is highly similar to aminopeptidase Y from P. aeruginosa 18A. It can be speculated that this enzyme is a Zn2+-dependent enzyme and contains two zinc ions in its active site. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding the use of indirect enzyme-linked immunosorbent assay (ELISA) for detecting duck reovirus (DRV) antibodies in duck serum.

The article presents a study on sequence analysis of 21 porcine reproductive and respiratory syndrome virus (PRRSV) isolates ORF5 and Nsp2 gene of 14 isolates amplified by reverse transcriptase polymerasechain reaction (RT-PCR) in Jiangsu, China. Result shows that the overall ORF5 gene isolates reaches 603 bp in length and the 21 isolates had an identity of 98.5%-100.0%. All the 14 isolates show 87 bases deletions at 2 947-3 033 and 3 bases at 2 778-2 780 of the VR-2332 Nsp2 genome analysis.

The article presents a study which discusses the construction of a recombinant Marek's disease virus expressing HA gene of highly pathogenic H5 AIV.

The hemagglutinin (HA) gene from H5N1 avian influenza virus and the chicken interleukin 2 (chiIL-2) gene were inserted into a expressing vector p12LS to construct a recombinant transferring vector p12LSH5AIL2, in which HA gene under the control of the promoter Ps was in inverse tandem connection with the chiIL-2 gene under the control of the promoter PE/L. The p12LSH5AIL2 was then used to transfect the chicken embryo fibroblasts (CEF) pre-infected with a wild-type fowlpox virus 282E4 strain, to generate a recombinant fowlpox virus coexpressing the inserted HA and chiIL2 genes (rFPV-H5AIL2). The rFPV-H5AIL2 was obtained and purified by blue plaque screening on the CEF. The in vitro expression of HA gene by rFPV-H5AIL2 was detected in the recombinant fowlpox virus-infected CEFs with an indirect immunofluorescence assay, and the expression of the chiIL2 gene by rFPV-H5AIL2 was confirmed by detection of the chiIL2 mRNA by RT-PCR and by detection of chiIL2 by the indirect immunofluorescence assay. Experiments on SPF and commercial chickens demonstrated that the titer for HI antibodies induced by the rFPV-H5AIL2 was significantly higher than that by the rFPV-HA. The group immunized with the rFPV-H5AIL2 exhibited the similar ratios of protective efficacy and virus shedding as the group immunized with the rFPV-HA in SPF chicken. However, in commercial chicken, the group immunized with the rFPV-H5AIL2 generated significantly higher protection against H5N1 avian influenza virus challenge and lower virus shedding than the group immunized with the rFPV-HA. This study paved the way for further development of a new AIV recombinant vaccine.

Objective: To investigate the change of glucagon-like peptide-1(GLP-1) and its effect on blood glucose metabolism after major surgery., Methods: Eleven patients, who had undergone major surgical procedures in our Department of General Surgery, were studied on the day before surgery, the first, third, and fifth day after surgery. Then, 42 rats were allocated randomly into three groups. The rats in control, which had not undergone any operation, received an intravenous glucose load (0.5 g/kg glucose + normal saline). The rats in operated group, which had undergone about 65% liver resection, received a same glucose load on the first, third,and fifth postoperative day. And the rats in GLP-1 group, which had undergone same hepatectomy, received a same glucose load with GLP-1 (0.3 nmol/kg) on the first, third,and fifth day after surgery. All rats would be killed by abdominal aorta exsanguinated in five minutes after drugs were infused of which the bloods were collected for determination of glucose (glucose oxidase), insulin, glucagon, and GLP-1 (radioimmunoassays) at each time-point., Results: There was an increasing postoperative plasma concentration of glucose, insulin, and glucagon on the first day (P < 0.01), but the plasma GLP-1 was just elevated on the third day (P < 0.05). Then, the plasma glucose concentration was significantly lowered after GLP-1 given to rats undergoing hepatectomy (P < 0.001), which might reach the glucose range in controls. Lowering of blood glucose was achieved by a significant rise of insulin secretion (P < 0.001) and a suppression of glucagon secretion (P < 0.05)., Conclusion: As far as can be concluded on basis of our data from patients and rats, GLP-1 can be used to reduce the plasma glucose concentrations when it is in stress status after major surgery.

Objective: To observe the effect of traditional Chinese medicine (TCM) treatment according to syndrome differentiation on acute radio-reaction (ARR) in nasopharyngeal carcinoma (NPC) patients., Methods: One hundred and ninety-five NPC patients who received radiotherapy (RT) for the first time were randomly assigned to two groups: the control group (89 cases) was treated by RT alone for 7 weeks and the treatment group (106 cases) was treated by RT combined with oral taking TCM from starting of RT till 5 weeks after RT. The overall changes in total ARR score and ARR in different locations were observed weekly and compared., Results: The total ARR score in the treatment group was significantly lower than that in the control group (P<0.05). And the ARR scores of different organs, including skin, oropharyngeal mucosa, salivary glands, larynx, car, upper digestive tract, and central nervous system, in the treatment group were all lower than those of the corresponding organs in the control group. In addition, the ARR scores in both groups showed an ascending trend in the first 7 weeks and a descending trend from the 8th to the 10th week after beginning RT., Conclusion: TCM treatment could relieve the ARR in the NPC patients without any affection on the efficacy of RT.

Based on the complete genome sequence of Newcastle disease virus (NDV) ZJI strain isolated from an outbreak in the goose, seven pairs of primers were designed to amplify cDNA fragment for constructing the plasmid pNDV/ZJI, which contained the full-length cDNA of NDV ZJI strain. The pNDV/ZJI with three helper plasmids, pCI-NP, pCI-P and pCI-L, were then cotransfected into BSR-T7/5 cells expressing T7 RNA polymerase. After inoculation of the transfected cell culture supernatant into embryonated chicken eggs from specific-pathogen-free (SPF) flock, infectious NDV ZJI strain was successfully rescued. The recombinant plasmid pNDV/ZJIFM was generated by converting the multi-basic amino acid sequence of the F0 protein cleavage region in pNDV/ZJI to the non-basic amino acid sequence characteristic of avirulent NDV strain. After cotransfection of the resultant plasmid and the three helper plasmids into BSR-T7/5 cells, the recombinant NDV, NDV/ZJIFM, was generated. The mean death time (MDT) of NDV/ZJIFM was more than 120h and the intrancerebral pathogenicity index (ICPI) was 0.16, indicating that the rescued virus was highly attenuated. This attenuated genotype VIId NDV of goose origin could be a desirable vaccine in controlling the current epidemic of ND.

Objective: To study the mechanism of ceramide-induced cellular signal transduction and its effect on renal injury., Methods: Sixty male Sprague-Dawley rats were randomly assigned to four groups (n = 15): control group, sham operation group, experiment group one and experiment group two. Except the control and the sham operation group, the other two experiment groups underwent the common bile duct bound to form the rat model of obstructive jaundice. The renal glomerular mesangial cells (GMC) were cultured primarily. After GMC were given different stimulating factors, we performed the measurement of the PLD activity and the GMC apoptosis analyzed by flow cytometry., Results: The biological activity of PC-PLD was significantly decreased by TNF-alpha and ceramide (P< 0.05). On the other hand, the GMC apoptosis was induced by TNF-alpha and ceramide (P <0. 05). However, other opposite results were obtained in addition of ceramide inhibitor to GMC., Conclusion: TNF-alpha can induce the ceramide increase in GMC, which is significant to effect on the kidney injury of the rats with obstructive jaundice, by the means of inducing GMC apoptosis and decreasing the activity of PC-PLD.

It has been reported that NA gene of some H1N1 Influenza A virus strains isolated since 1933 is characterized by a deletion of 11 to 16 amino acids in the stalk. The spontaneous mutant in NA stalk of H1N1 virus lacks enzyme activity with large substrate (fetuin) but not with small substrate (sialyllactose). Recently, H5N1 virus also has been found that NA has the same unique mutation in the stalk, a deletion of 15 to 20 amino acids. However, biological significance of this mutation has not yet been reported. In order to investigate biological significance of the amino acids deletion in NA stalk of H5N1, five reassorted H5N1/PR8 viruses were generated via eight-plasmid based reverse genetics system. These five viruses were named 506, m506-, 646, m646+ and 196, respectively. The six internal genes of recombinants were all from A/PR8/34(H1N1), and HA gene was from A/G/JS/03(H5N1), however, they had different NA genes. 506 and m506- held NA fragments derived from A/G/HD/00(H5N1), and the former was distinguished with a longer NA which had no 20 amino acids deletion in the stalk. 646 and m646+ held NA fragments from A/G/JS/03(H5N1), and the NA stalk of m646+ was 20 amino acids longer than that of 646. The NA of 196 was derived from A/PR8/34 which had 15 amino acids deletion in its stalk. Biological characteristics of these viruses showed that recombinants with different NA length could grow well in embryonated SPF eggs, and their EID50, MDT, and viral titers were similar. However, the length of NA was related to the capacity of eluting viruses from erythrocytes for 506 and 646+ which holding longer NA stalks eluted from erythrocytes more quickly than m506-, 646 and 196 did. Moreover, 15 or 20 amino acids deletion in NA stalk had a pronounced effect on virus growth ability in MDCK cells. Viral titers in supernatant of MDCK infected with m506- or 646 were 10 to 100 folds higher than those infected by 506 or m646+. And the plaque size of m506- and 646 were larger than that of 506 and m646+. The results reveals that H5N1 AIV with amino acids deletion in NA stalk would expand its host range. The unique amino acids deletion in NA molecule of H5N1 may be associated with the adaptation of virus to terrestrial poultry or the increasing ability of interspecies transmission.

H5N1 subtype influenza virus A/Duck/Shandong/093/2004 (A/SD/04) strain was chosen as the master strain for rescue research. 11 sets of primers for 8 plasmids construction were designed base on the sequencing of the full-length of A/SD/04. Eleven fragments of A/SD/04 were amplified by the designed primers and were ligated with PHW2000 for rescue plasmid construction. Eight transcription/expression plasmids were obtained, which encoded the eight segments of A/SD/04, and designated as 241, 242, 243, 244, 245, 246, 247 and 248, respectively. The COS-1 cell was cotransfected with eight plasmids with different combination of A/SD/04 and PR8. The eight reassortants shared the same HA (from A/SD/04) but contained different internal genes and NA. All of the eight reassorted viruses had some similar bio-characteristics, such as the viral title in fertilized eggs was range from 256 to 1024, the EID50 were between 10(-8.5) to approximately 10(-9), and MDT were between 34 to approximately 46h. But the IVPI of the eight reassortants was differently and all were lower than the wild-type A/SD/04. These results confirmed that different recombination of internal genes of H5N1 has influence on viral virulence to 6-week SPF chicken but not on viral replication ability in embryonated chicken eggs. The establishment of eight-plasmid rescue system for A/SD/04 is the base for farther research on genes function of H5N1. And A/SD/04 can be used as a backbone to replace PR8 entirely in generation of H5 AIV vaccine candidate.

The full-length cDNA clone, NDV3GM122, and the three helperplasmids pCI-NP, pCI-P and pCI-L of Newcastle disease virus strain ZJI isolated from an outbreak in the goose were cotransfected into BSR-T7/5 cell expressing T7 RNA polymerase. Meanwhile, the full-length cDNA clone NDV3GM122 and the three helperplasmids, pCIneoNP, pCIneoP and pCIneoL which were derived from NDV strain La Sota, were also cotransfected into the cell, respectively. Indiect immunofluorescence assay (IFA) was performed 48 to 96 hours post-transfection using NDV HN-specific monoclonal anbtibody (McAb) 6B1 and bright stainings were found in the transfectants, indicating that the full-length clone was functional and the HN protein was expressed. The transfected cell and the supernatant were mixed well and thereafter the mixture was inoculated into specific pathogen free (SPF) chicken eggs. The allanotoic fluid of the injected eggs gave a positive hemagglutinin( HA) titer ranging from 16 to 32 in the secondary passage and increased to 128 in the third passage, which was same to the level of parent wild-type virus. The allantoic fluid containing the recovered NDV was analyzed in hemagglutination inhibition( HI) test by using McAb 6B1 and the specific inhibition was found. The typical morphology of the produced NDV was detected in the electronic microscope. The results mentioned above demonstrated that infectious NDV of strain ZJI was successfully generated, which laid good foundation for the further related research.

Background: To evaluate feasibility and safety of venovenous bypass prior to mobilization of the liver during orthotopic liver transplantation (OLT)., Methods: Fifty-four patients were classified into two groups. Group A consisted of 23 patients receiving OLT with classical venovenous bypass. Group B consisted of 31 patients who received a modified-procedure: venovenous bypass ahead of the mobilization of the liver during OLT. The blood loss, duration of venovenous bypass, cold ischemia time, anhepatic phase, and transfusion during operation in the two groups were compared. Complications after the operation were also compared between the two groups., Results: The duration of venovenous bypass and cold ischemia time in group A were longer than those in group B [(99.78+/-21.36 min) vs (96.32+/-22.25 min) and (484.78+/-134.01 min) vs (443.15+/- 85.27 min)]. The anhepatic phase lasted for about 100 min averagely in the two groups. The volumes of blood loss and transfusion during the operation were larger in group A than in group B [(5096+/-4243 ml) vs (1726+/-1125 ml) and (3676+/-2938.74 ml) vs (1217.69+/-829.72 ml)]. Postoperative complications occurred in 26 patients of group A and in 19 patients of group B., Conclusion: This modified-procedure or venovenous bypass ahead of mobilization of the liver in OLT can reduce the blood loss during OLT and the incidence of postoperative complications without prolongation of the anhepatic phase and duration of venovenous bypass.

AIM:To evaluate hepatic energy charge levels of the patients with hepatoma after hepatic artery embolization and its relation to postoperative complications.METHODS:Sixty-nine patients with hepatoma were continuously measured for their arterial blood ketone body ratio (AKBR) and compared with their postoperative clinical course or conventional liver function test after various hepatic artery embolization.RESULTS:AKBR in high radiation dose or jaundice group drastically decreased at 1-3 days and recovered slowly. Patients were classified into three groups according to the value of AKBR: group A (35 cases), AKBR remained higher than 0.7; group B (31 cases), AKBR had transiently dropped to 0.4-0.7 and then increased to preoperative value; and group C (3 cases), AKBR decreased steadily to below 0.4.The occurrence rate of various complications were 5.7%, 32.3% and 100% in the three groups, respectively (P < 0.005).CONCLUSION:The AKBR which reflects hepatic mitochondria redox state is more reliable as a direct indicator to assess hepatic tolerance for embolization than routine liver function test.