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Jian Lu

Publications and source records attributed to Jian Lu.

70 records · Page 4Linked to original sources
PubMed2002

[Molecular phylogeny of Drosophila auraria species complex].

Drosophila auraria species complex consists of five sibling species D. auraria, D. biauraria, D. triauraria, D. quadraria and D. subauraria. The complete sequences of nuclear ITS1 (internal transcribed specer 1) and mitochondrial CO II (Cytochrome Oxdase II), and partial sequences of nuclear Adh (alcohol dehydrogenase) of these five sibling species and their closely-related species, D. rufa, were determined. Using D. rufa, D. melanogaster and D. yukuba as outgroups, both most-parsimony (MP) and neighbor-joining (NJ) trees were constructed based on the sequences of each genetic marker. In each tree, D. subauraria always branched off first within Drosophila auraria species complex. Combined sequences of ITS1, Adh and CO II are 2327 bp (excluding gaps), of which 255 sites are parsimony informative. Phylogenetic analyses based on the combined data sets can resolve the phylogenetic relationships of the five sibling species relatively well. According to the MP and NJ trees based on the combined sequences, D. subauraria was the first to emerge within Drosophila auraria species complex, thereafter D. biauraria branched off, D. auraria, D. triauraria and D. quadraria had a relatively recent speciation history. In this paper we propose a hypothesis about divergence events in Drosophila auraria species complex: The ancestor of this species complex diverged with D. rufa in warm-temperate regions about 2.33 myr ago, then they invaded into cold-temperate regions. In cold-temperate regions, D. subauraria was firstly derived from the ancestor of Drosophila auraria species complex about 0.88 myr ago, thereafter D. biauraria emerged about 0.31 myr ago. During the process the ancestor reinvading into warm-temperate and subtropical regions, speciations of D. auraria, D. triauraria and D. quadraria were gradually completed. This hypothesis does not agree on the previous opinion that D. quadraria was the ancestral species of Drosophila auraria species complex.

Alcohol Dehydrogenase↗
PubMed2002

[RhoA gene expression in colorectal carcinoma].

OBJECTIVE: To investigate the expression of RhoA mRNA in colorectal neoplasms. METHODS: Total RNA was extracted from 42 surgically resected specimens of colorectal caricinoma and normal mucosa close to the lesions. Afier the optimal reverse transcription polymerase chain reaction (RT-PCR) condition was found, the mRNA expression levels of the RhoA gene in the lesions and the normal mucosa were examined semi-quantitatively and the relation between these expression levels and clinical pathological markers was compared. RESULTS: The expression of RhoA gene mRNA in lesion of colorectal carcinoma was significantly higher than that in contiguous normal mucosa (1.8 +/- 0.6 vs 0.9 +/- 0.4, P < 0.01). The ratio of RhoA expression in neoplasm to that in contiguous mucosa was 2.02 +/- 0.82. Based on this ratio the 42 patients were divided into two groups: overexpression group (19 cases) and high-expression group (23 cases). In the overexpression group the lesions of 14 cases were in Dukes C and Dukes D stages, and lymph node metastasis was found in 13 cases. In the high-expression group, only 9 out of the 23 cases were in advanced stage and 8 cases showed lymph-node metastasis. Chi-squared test analysis demonstrated a significant difference in both aspects between these two groups (P < 0.05). The difference in number of metastatic lymph nodes between the two groups was statistically significant (P < 0.01). Mutation was not found in the RhoA gene sequence examined. CONCLUSION: RhoA gene may play an important role in colorectal carcinogenesis and correlate with invasion and metastasis of colorectal carcinoma.

Adult↗
PubMed2002

[Immunogenicity of recombinant HEV ORF2 protein expressed in pichia pastoris].

BACKGROUND: To study to immunogenicity of recombinant HEV ORF2 protein expressed in pichia pastoris. METHODS: BALB/c mice were immunized with the recombinant HEV ORF2 protein. The ability of antiserum to bind HEV was tested using affinity-capture reverse transcription polymerase chain reaction (RT-PCR). Moreover, the recombinant protein was used to immunize BALB/c mice by different routes with different adjuvants. Serum conversion rate of anti-HEV antibody and the ELISA titer were detected. RESULTS: The antiserum could capture native HEV for RT-PCR. As to the immunization effect, the immune response by intramuscular route was better than that of the intraperitoneal route. The protein with alum and CpG adjuvant could elicits more significant immune responses than using the alum adjuvant alone. The best way was to immunize with the protein with alum and CpG adjuvant by intramuscular route with a boosted injection on the 4th week after the first immunization. The ED50 was 0.023 microgram. This is the first report that the antibody elicited by recombinant HEV ORF2 protein expressed in pichia pastoris recognizes native HEV. High immunogenicity of this kind of ORF2 was also demonstrated by inducing strong immune response in mice with good ED50 result. CONCLUSIONS: The high immunogenicity of this kind of HEV ORF2 may make a foundation for the development of new type of hepatitis E vaccine.

Animals↗
PubMed2002

[Preliminary evidence that a hepatitis E virus (HEV) ORF2 recombinant protein protects cynomolgus macaques against challenge with wild-type HEV].

BACKGROUND: To observe the protective effect of hepatitis E virus (HEV) ORF2 recombinant protein expressed in prokaryote cell cynomolgus macaques (cynos) against challenging with wild-type HEV. METHODS: Cynos were immunized with HEV ORF2 recombinant protein and then challenged with wild-type HEV, the unimmunized cynos were used as control. Blood samples were collected and tested to see if there were dynamic changes of ALT and antibody to HEV before and after challenge with wild-type HEV. RESULTS: All the five unimmunized cynos re-presented hepatitis 3 weeks after challenging with wild-type HEV. However, all the five immunized cynos showed no hepatitis and pathological changes. CONCLUSIONS: Cynos can be efficiently protected by immunization with HEV ORF2 recombinant protein against wild-type HEV. This protein can be a promising candidate for HEV vaccine.

Animals↗
PubMed2002

[Cadaver renal transplantation and multivariate analysis for graft survival: a clinical review of 2 016 cases].

OBJECTIVE: To review kidney transplantation in the center and analyze the risk factors affecting long-term allograft survival. METHODS: Thirty-two relative variables were analyzed with SAS statistical software. Using Log-rank method, we investigated influence of these variables on short-and long-term survival of grafts. Kaplan-Meier analysis was used to estimate the 1-, 3-, 5-, 10-years graft survival rates and half-life. Proportional hazards regression analysis (Cox model) was used to assess and rank the relative risk of potential variables. RESULTS: The 1-, 3-, 5-, 10-years graft survival rates were 83%, 75%, 66% and 48%. After excluding the patients died with functioning grafts, the 1-, 3-, 5-, 10 years grafts survival rate increased to 89%, 82%, 75% and 69%, respectively. The mean half-life was 8.78 +/- 0.14 and 14.09 +/- 0.20 years, respectively. By Log-rank analysis, factors affecting short- and long-term graft survival were identified as: renal function, duration of graft function became normal, cold-ischemia time, presence of acute rejection, delayed graft function, immunosuppressive regimen, complication, infection, anti-rejection therapy. Cox model multivariate analysis showed that there were 18 factors affecting graft survival. CONCLUSIONS: New immunosuppressive agents not only significantly increase short-term graft survival, but also have the better long-term outcome tendency. Making assurance to get high quality donor organ and minimizing the death with graft function may be the most feasible way to prolong graft survival at present.

Adult↗
PubMed2002

[Rapid inhibition of extracellular signal-regulated kinase 1/2 in a human ovarian cancer cell line by dexamethasone].

BACKGROUND & OBJECTIVE: Activation of extracellular signal-regulated kinase 1/2 (ERK1/2) plays an important role in cell proliferation of a variety of cell types. The authors had previously found that dexamethasone (Dex), a synthetical glucocorticoid, can markedly inhibit the proliferation of a human ovarian cancer cell line HO-8910. This study was designed to observe the effect of Dex on the activation of ERK1/2 in HO-8910 cells in order to explore the signal transduction pathway that mediates the anti-proliferation effect of Dex on these cells. METHODS: The activation of ERK1/2 was determined by Western blot analysis, and changes of cell proliferation were examined by cell count. RESULTS: Inhibition of activation of ERK1 and ERK2 by 1 x 10(-7) mol/L Dex occurred synchronously at 5 min, with maximum up to 41% and 54%, respectively at 30 min compared with the control (P < 0.001), and sustained until 4 h. The effect increased with the increasement of concentration of Dex (1 x 10(-10)-1 x 10(-6) mol/L). RU486, an antagonist of glucocorticoid receptor (GR), did not block the effect. PD98059, an inhibitor of MEK1/2, also inhibited HO-8910 cell proliferation and could enhance the growth-inhibition effect of Dex. CONCLUSION: Dex can rapidly inhibit ERK1/2 activation in a GR-independent manner in HO-8910 cells, which might play a role in Dex-mediated growth inhibition.

Antineoplastic Agents, Hormonal↗
PubMed2002

[Improvement of recombinant xylanase XynF1 from Aspergillus oryzae expressed in Pichia pastoris by site-directed mutagenesis].

The recombinant xylanase XynF1 from Aspergillus oryzae expressed in the methylotrophic yeast Pichia pastoris was improved by site-directed mutagenesis. The mutant I156A secreted about 47.7 U/mL xylanase XynF1 in the BMMY medium. The mutant xylanase XynF1 was purified by ion exchange and gel filtration chromatographies. The molecular weight of purified XynF1 was 35 kD. XynF1 was stable between pH 4-9 and its optimum pH was 7.0. The optimum temperature of XynF1 was 45 degrees C and it was stable below 50 degrees C. The properties of mutant were same as the parent's except the stability of temperature.

Aspergillus oryzae↗
PubMed2002

[Pulmonary delivery of insulin lipid suspension].

AIM: To investigate the relative bioavailability of pulmonary-delivered insulin lipid suspension (INS-LIP-SP) in normal Wistar rats. METHODS: INS-LIP-SP were prepared by two different methods and then delivered to the rat lung using an intratracheal instillation method. Blood glucose levels and INS concentrations in serum were determined by glucose oxidase method and radioimmunoassay method, respectively. The relative pharmacological bioavailability (f%) and relative bioavailability (F%) of INS-LIP-SP were calculated from the area above the curve (AAC) and the area under the curve (AUC) compared with subcutaneous injection of INS solution. RESULTS: The mean particle diameter, span of dispersity and entrapment efficiency of INS-LIP-SP prepared by a membrane-formed with sonication method and a reversed phase evaporation method were 1.91 microns, 0.94 and 16.45% and 2.08 microns, 1.28 and 39.51%, respectively. The values of f% and F% of both INS-LIP-SP were up to 37% and 32%, separately, and there was a statistically significant difference between INS-LIP-SP and INS solution. However, there was no significant difference between the two INS-LIP-SP and the physical mixture of INS solution and blank liposomes. CONCLUSION: The results showed that INS-LIP-SP could achieve higher bioavailability following pulmonary delivery to rats.

Administration, Inhalation↗
PubMed2002

[Vaccination of rhesus monkeys with recombinant antigen fragments and protection from hepatitis E virus infection].

OBJECTIVE: To observe anti-HEV IgG response to vaccination of recombinant antigen fragments and evaluate its protection from Hepatitis E Virus infection in rhesus monkeys (Macaca mulatta). METHODS: Twelve monkeys were divided into three groups and immunized respectively with three different recombinant antigens: namely Ag1 (carboxyl terminal 431 amino acids of ORF2), Ag2 (128aa fragment at the carboxyl terminal of ORF2), and Ag3 (full length ORF3 ligated with two ORF2 fragments encoded by 6743-7126nt and 6287-6404nt). The monkeys were challenged intravenously with fecal suspension from experimentally infected rhesus monkeys, and the other three monkeys served as the placebo group for challenge with HEV. The dynamic changes of the levels of ALT and anti-HEV IgG were examined. Pathological changes of liver tissue were observed by light microscope. Excretion of virus was detected by RT-nPCR. RESULTS: Hepatic histopathology of two monkeys in the placebo group was consistent with acute viral hepatitis, and ALT was elevated 3-4 weeks after inoculated with virus, up to 10-20 times higher than normal level. The liver tissue of monkeys immunized with antigen kept normal, ALT in several monkeys elevated mildly, and anti-HEV IgG conversation occurred at 1-2 weeks after vaccination, with the titer reaching 1:12,800. The virus RNA could be detected by RT-nPCR from days 7 to 50 in monkeys of control group, and from days 7 to 21 in vaccinated monkeys after challenged with virus. CONCLUSIONS: The recombinant antigens could induce the production of anti-HEV IgG, which protected rhesus monkeys from acute Hepatitis symptoms related to HEV infection.

Animals↗
PubMed2002

Detection of anti-MHAV and anti-MHEV IgM in patients with sporadic acute hepatitis in Beijing between 1995-2000.

OBJECTIVE: To investigate the age range, liver function damage and prognosis of patients with sporadic acute hepatitis A and E in Beijing. METHODS: Enzyme immunoassay (EIA) was used to detect anti-HAV and anti-HEV immunoglobulin M (IgM). Serum samples were collected from the patients with sporadic acute viral hepatitis in Beijing from January 1995 to June 2000. RESULTS: The total Positive rate for anti-HAV and anti-HEV IgM was 55.2% (112) in 203 patients with acute hepatitis, of whom 22.2% (45 patients) and 33.0% (67) were positive for anti-HAV and anti-HEV respectively. The duration of anti-HEV IgM was 45-60 days and that of anti-HAV IgM was at least 2-3 months. The patients with acute hepatitis A and hepatitis E all experienced jaundice and a rising of liver enzyme, but did not develop chronic hepatitis or died. CONCLUSION: Acute hepatitis A as well as acute hepatitis E plays an important role in sporadic enterically transmitted hepatitis in Beijing.

Acute Disease↗
PubMed2002

[Observation on the effect of curettement-adhesive on submucous resection of nasal septum].

OBJECTIVE: To explore a method of how to handle the wound in submucous resection of nasal septum (SMR) so as to improve the effect of the operation. METHOD: 83 cases with deviation of nasal septum underwent the operation of submucous resection of nasal septum. Then they were divided into two groups at random. One group as curettement-adhesive group (42 cases) were treated by biological adhesive solvent (BAS) to the wound after submucous resection of nasal septum without a tamping to the nasal cavity. The other group as control group (41 cases) was treated by Vaseline gauze packing. Then the postoperative reactions and effect in each group were compared according to the degree of headache, hyperaemia of nasal mucosa and edema of nasal mucosa. RESULT: There were a distinct difference of the degree of headache, hyperaemia of nasal mucosa and effect in curettement-adhesive solvent group to the other group. CONCLUSION: The use of BAS in SMR can simplify the operation and shorten the rehabilitation time. It can relieve the postoperative reaction and reduce syndromes. So it is worth researching.

Adolescent↗
PubMed2000

Mutations in the N-terminal Transcriptional Activation Region of Androgen Receptor in the Chinese.

Activation function (AF1) region of N-terminal domain of androgen receptor (AR) is necessary for the transcriptional activation function of AR. The sequences of AF1 in twenty normal chinese were amplified by PCR and determined by direct dsDNA cycle sequencing. Based on this, the mutations in AF1 of AR in patients with androgen insensitivity syndrome(AIS) or prostate cancer(PC) were screened by a combination of single strand conformation polymorphism(SSCP) analysis and direct dsDNA cycle sequencing. The sequences between normal chinese and other races were identical and one point mutation (C966A, Ser296Arg), which had not been reported so far, was identified in a patient with prostate cancer with poor differentiation. That suggests alteration of structure and function in AF1 of N-terminal domain of AR might be relative with PC progression of some patients.

Journal Article↗
PubMed1998

One-Dimensional Coordination Polymers of Cobalt with 4,4'-Bipyridine: Syntheses and Structures.

Several new one-dimensional coordination polymers were obtained by reactions of different simple cobalt salts with 4,4'-bipyridine. Co(SO(4))(H(2)O)(3)(4,4'-bipy).2H(2)O (1) was obtained by reacting CoSO(4) with 4,4'-bipy in a water/ethanol solvent system: hexagonal, P6(5), a = 11.435(2) Å, c = 20.886(4) Å, Z = 6. CoCl(2)(DMSO)(2)(4,4'-bipy) (2) was crystallized from the reaction of an aqueous solution of CoCl(2) with a DMSO solution of 4,4'-bipy: orthorhombic, Pbcn, a = 11.470(2) Å, b = 11.390(2) Å, c = 14.753(1) Å, Z = 4. Reaction of Co(CH(3)COO)(2) with 4,4'-bipy in water/acetonitrile under hydrothermal conditions yielded Co(CH(3)COO)(2)(4,4'-bipy) (3): triclinic, P&onemacr;, a = 7.996(1) Å, b = 9.128(1) Å, c = 10.676(1) Å, alpha = 109.79(1) degrees, beta = 99.90(1) degrees, gamma = 100.98(1) degrees, Z = 2. 1 and 2 have structures containing linear Co-bipy-Co chains. In 1, the chains are connected by a network of hydrogen bonds. The structure of 3 contains linear double Co-bipy-Co chains bridged by CH(3)COO(-) groups. The reaction chemistry observed in different solvent systems and under hydrothermal conditions is discussed.

Journal Article↗
PubMed1998

Construction of a Helper-dependent Adenoviral Vector and Its application to Mice.

First-generation adenoviral vector with E1 and E3 deleted can effectively deliver foreign genes into target cells and leads to high level of expression of transgenes, but it leads only to transient expression because of the cellular immunity against early and late viral antigens expressed in targeted cells. In order to overcome these difficulties, we have recently developed a helper-dependent recombinant adenovirus vector HAdI-hFVIII in which a large part of the viral genome, including l3, L1, L2, VAI-VAII and pTP regions, was deleted. The novel viral vector DNA can be effectively packaged, amplified in 293 packaging cells co-transfected with an E1-substituted AdI-hFVIII in trans and can be easily separated from helper virus by gradient centrifugation. The hFVIII expression was found in mice after intravenous injection of the new vector. The duration of hFVIII protein in plasma of mice was prolonged compared to that of AdI-hFVIII after injection. It suggests that the novel vector could be less immunogenic in vivo.

Journal Article↗
PubMedDate not supplied

GABAergic phthalide dimers from Angelica sinensis (Oliv.) Diels.

The methanol extract of Angelica sinensis (Oliv.) Diels roots (Dang Gui) has been shown to exhibit competitive binding to the GABAa receptor, suggesting the presence of GABAergic ligands. Chromatographic fractionation of the methanol extract led to the isolation of two GABAergic dimeric phthalides 1 and 2. Gelispirolide (1) was elucidated as a new phthalide dimer composed of a Z-ligustilide and a Z-butylidenephthalide unit on the basis of spectroscopic approaches including one- and two-dimensional NMR, HRESIMS and HRESIMS-MS. Compound 2 was identified as the known dimeric phthalide, riligustilide, by comparison of its spectroscopic data with literature values. Its dimeric linkage and stereochemistry were ascertained by a single crystal X-ray diffraction experiment. Both dimers 1 and 2 were found to be active in an in vitro GABAa receptor-binding assay with IC50 values of 29 and 24 microM, respectively.

Angelica sinensis↗